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He sounds like he gets out of bed in the morning and is absolutely thrilled he gets to do more math, every single morning

"Give me a prime" "2^31 - 1" Baller move. Brady should do that the next time Matt Parker asks for a number

Neil Sloane is always worth my time.

Seeing Neil Sloane enjoy his sequences (and talk about them) is always a pleasure. Please do more interviews with him in the future!

The largest prime that I know the digits of is Belphegor's Prime: 1 0000000000000 666 0000000000000 1 Thirteen zeros before and after the number of the beast, 31 digits (13 reversed) in all.

He always seems like a child who has found something interesting to play with 😍

@numberphile hey! I saw this and thought, "what about concatenating increasing values to the left" i.e. 1,21,321,4321,54321, etc. Did a little bit of number crunching and the first one I found was at a starting value of 82. They exist! (I was able to speed up my search realizing that 2/3 of these are divisible by 3 and skipping testing those.) Maybe look for the next one and make a video on it? Prime related videos are always a hit. :) Anyway.... Loved this video! It inspired the little search I just did.

Great, now I can boast about knowing a 17000-digit prime by heart! Thanks

4:39 "I'm not finished. I have another segment." I don't know why, but I really enjoyed that. He loves and can talk about numbers all day.

I got curious and decided to try this - but with base-2 instead of base-10. And I think I found one! 01101110010111011110001001101010111100110111101111, which is 485398038695407, _is a prime_. And it contains the numbers from 0 (which might as well not be there) to 15.

I would love to hear more from this gentleman, he can be a narrator for some great shows

Just an FYI, CCS is pretty much just a waste of money, and has never been demonstrated to be effective at reducing CO2 emissions.

He better live to a hundred or I'm gonna cry

"It's a story you can tell at parties." I'd love to go to a party where I get to hear Neil Sloane's stories!

Prime numbers and numberphile videos about them , never get old

I'm intrigued by the sequences both so important and so hard to evaluate that they have the privilege to be included in the OEIS with only one entry. Tell us more about that please !

The professor has such a beautiful voice.

I would like to note that if the step between each number is 2 instead of 1 (so 135... instead of 123...) the first prime is 13, but the first interesting one is 135791113151719

Now I'd really like to know which sequences in the OEIS contain a single term

I expect the most wanted prime number is the private key to some big bank's signing certificate, but this is maybe the coolest (to mathematicians)

My new favorite hobby is reading all the comments on "the all 1's sequence" on the oeis.

Huh, this is interesting... I actually got 2 "most wanted primes" in hexadecimal with n < 1000, the first is 123456789ABCD (n = 13) and the other is much larger (n = 211)

can't wait to whip out this story at a party

I hope I'll have his energy at his age. Just a joy to watch.

So happy to have Neil back

by the books in his shelf it´s nice to see Professor has also an interesting in Operating Systems (Unix) and computer programming (Shell)

I can't bear the sound of that sharpie pen writing on that rough paper!

I love these videos with Neil Sloane. It's very soothing to hear him describe patterns.

I love the fact Neil has a ping pong table as a desk.

Brady: Should we believe there are an infinite numbers of n's this will work for? Neil: Yes, do the math. Me: I don't think I will.

I was just binging all of the old Neil Sloane videos yesterday. So glad to see a new one!

I love your videos with Neil. Hands down my favorite guest on the channel!

@3:40 I'd love to watch a video of these 1-term sequences!

I love Sloane's enthusiasm, it's infectious.

This is an absolute gem. Thank you.

Me: "Is this prime?" Mathematicians: "hmm, not sure... BRING OUT THE GIMP!!!!!"

Neil: I encourage everyone to continue the search and find that smallest value of n which is prime. Me: Or prove such an n doesn't exist?

Great video.. more of Neil please.

Thank you to Numberphile for showing me the beauty of mathematics. I was in high school learning algebra when I was also watching Parker et Al and understanding little, but appreciating the beauty seen by the presenters. Thanks Brady.

I always want more Sloane content!

This is why I love numberphile !

I liked Neil's little moment of flailing, frustrated at being unable to find any primes.

This is gold. A true KZfaq treasure.

Neil is an absolute treasure, and it’s always pure joy to watch numberphiles when he is in an episode!

Nearly 4m subscribers, nice work. Hope you've got the special ready

God I hope you have 100 Neil Sloane videos backlogged. This man is my math grandfather. What a treasure.

Your enthusiasm is SO contagious. 😁

The way he enounciates question is oddly soothing

A petition to authorise 1 to be a prime number would solve this problem easily!

For the most wanted prime it's interesting that not only are n%2=0 definitely not prime. but because 10%3=1, also n%3=0 will definitely be divisible by 3 as the last one was and n-2+n-1 is divisible by3. But this carries over to n%3=2 as we know that the next number is divisible by 3 and that a multiple of 3 was added.

Neil is a joy to listen to

Loved how all his books and file folders are labelled and organised. 😍

I really hope this video helps find the first prime like that.

Yeaah, Neil Sloane the Legend

His enthusiasm is infectious

“Bring out the Gimp” “But the Gimp’s sleeping” “Well, you’ll just have go wake him up now won’t you?”

So why did Armand Borel want a prime of 20 or more digits? What was he planning to do with the answer? We never found this out. (BTW, is Armand related to Emile Borel of the Heine-Borel Theorem?) Fred

I'm always suspicious of messing around with functions that only work in base 10. It's not that this isn't a real problem that could be solved, it's just more than it feels like numerology instead of mathematics.

I love the way he says, “Sorry!”

In base 3, not in OEIS, for most wanted primes (or pseudoprimes), you have: n=2 12 5d n=5 12101112 3929d n=82 121011122021221001011021101111121201211222002012022102112122202212221000100110021010101110121020102110221100110111021110111111121120112111221200120112021210121112121220122112222000200120022010201120122020202120222100210121022110211121122120212121222200220122022210221122122220222122221000010001 112472248900628264609109603739848048285897664360560828256938844196881901607705808202739737387845865591848483833175481611716989149644798597217d n=2546 12...a 17096 digits base3 number and in decimals: 43890161488751460546626702438613565060003336281644449680671137248224514688491538690975134899736580108040235144902850247124275888829167582111888208962431881069187554719673572324004400907342770369694358050895638847024397795010971505542791197193876977453786100380941871966222470323265996374093675914641362678086425952662353480926826428446406757377963278157666201416261682611228802339238477428776727632017540989988176195868147174041239187417604219543007022139243321058577590644959401984067191769030638388726906644028086903822159080075772603841931016576581760214138320362816303048679719547048722501702555633000390530689374516513680029408176364910292994228954902928969448658904462575577354071270800213912051201523507394365683111528565341198912876422694722144929638945967403245098708248404322530202727882676941072079153569222949337103192425966055684814431400044565451265813686761215405533643511789884617646328246743281720432328194095683194587785547508148773470772593738258801763760546794662073718516191928591072734651560403556002732524161730316142686268758260877916597511512003796528274036447792924499494864342440677602583759931789321793424298317396285449554955292586535836216021617023243141250119118512285946506249761293344929001780039983261592084263554914364441749840728216443011119067342706727925477712618231168978833958062652687921812610479346345264504765110030520074975442528118698445700483939782752609726084487308375967269514211813640018741875722580241863926703050300712545815352393120793488218413283618123570588307416854433864996494431522281803030485486558059502715089759852450544339517757804285967188699401114866728876776549756684736309852094725050865930800167370104933949388035243022389363378334680013923434066416861926258085816117742505281123833405809310964323493563189361527117878499659063347307304583402070651167772180308830540838123475351447507484992450520788644591125264607612093737901470944162813780897645548146351246209624486034557431548471720783210675389095371393790498285892636128668119451378240219077207134739752608785181867928263686385935215347914452582657142085011407738559212460959268691200770239157870204451164934062213679157927231503425082141878027811193566696609165091454874475721882598283385158300240762055794266047495929993818891307012591626969301205165344706934338840173319948265753741137524920248111206491006196652417307431031750699528179185458982562133803404685438296067156978853797336545647449025239991977998712697711265249729376743473555059777964135291443181725783056729552750299424308449273341836036581351481308211339703462171182093726530237263185892498101223377615500102312287248676936254608602229951158919989223765609446436479541916679149534365897182729707823017267283647397249900179384121021898332183399958586514174894501681280555416335242257069223054397177949751294731391574786389724838624019993383653689742946081760774109640742133417696582657530590909815179785635202106593346231901503857163231028136378224240545656107266082808509457244118432204364596748383545879295806117994595023772406415351247964030765052022307194245969684455877572521087343566249732952806269934334054705784570846540141977666647354223473972311288950609815860735838654476360384691259636542129738992987380417603981271846261521786588916834646357350934099126326728075067337322798596076189544486832952920264198426068039988068169743237688209371000314234636523906102826099011519696179003630302866491680295287097128551313032321293575929024306470092686558080746952275770835242360570930045228655204576322734523342849052530545974405199343183221590087859245300764078222862815288814207734442339460433012421856546439636266561975265503963066109237076379991393306132398275447039070424867309968987904427684423182702897381433098932224788146285245889721026254508998483143595198863424120430654450975773068603745141757057977594415814586925209888338894214617342925205156757352253040101332858321041516894759139574456898613064389079736487560664739435400868746702620299006861572577151088668428749705450014329385374165101664130899422691170661920102396003411157789363281244422411600247564749697988094095262218593242044279180823572957717109170056955699914724723828165141430769892345712501881108903022320421347100915124530872659403994296038150640065718827635199663190949646987849434145501509659086015263008665371714705277624397492086356504877074559834335005436733963222261337612984566084807359523673372914839433015018204943015330352599696510122346029749468281071434723897520884700709191513862252461006982884464210303147568253751881662056607466471401070638950718477367116659142364146394792699568224426051748009604323467662327479747880571417801026259794347390730849724019238094760895260627018391357674427100142529722180028599049119447849087294169503878161683194602136375471716666525377771670869918484418229582194639066294750852576218974124745820546263757377303828449999556216249892265725720667654811037842088818263095350793091393616240732601285395184407013946743728609257903977255811712828611203851591483970281282366272387476098249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Very base-10 heavy. The number 12345678910987654321 is indeed very memorable, and a nice piece of trivia at a party, but it seems like nothing particularly special because the fact that we write in base 10 is so arbitrary. I'd be curious to know if we wrote in base-12, for example, or base-n, whether either palindromic sequences or sequences that stop at n would be prime.

Time for a part 2 where Matt Parker writes some python code and almost finds one which we can call a Parker prime

Neil is great and he is obsessed with prime numbers. Please show more of his videos.

As always, captivating, educational and entertaining. 😊👍

My favorite thing about all of the numbers where n is less than 10, they are all square numbers. The coolest part is that the square roots of all of them are all composed of numbers made of 1s

2:40 Ten works! And 2,446! And beyond that we don't know... But we DO know there are an infinite number of them! And THAT's why I love Numberphile so much!

Yes the legend is back

after this i feel an immense need to go find that prime

N has a lot to answer for in mathematics. There is a huge weight on it's shoulders.

Maybe it’s just his genuine enthusiasm for the subject he’s discussing, but Neil reminds me a lot of Richard Feynman in his mannerisms and speech.

I love that Brady always films Neil Sloane in a Whataburger.

Every video of numberphile is so informative and enjoying, surely a boon for math lovers.

This climeworks actually sounds like setting up a timebomb for future generations.

GIMP is a graphics program. GIMPS is looking for primes.

Niel Sloane lifts my spirits.

best video on numberphile

I wonder if it is the "prime" accused in a crime?

I always find this type of sequence (that relies on a specific numeric base) kind of "meh". _Relevant_ stuff in maths is about _values_ and their properties, not about the characters you use to write them with. If the "property" you're looking for only works in base 10 but disappears in base 11 or base 8 or whatever, it's just a curiosity. It might tell you something interesting about that base (and that is especially true for base 2, which overlaps with logic / boolean algebra), but not really about the number sequence itself.

Wonderful!

he sounds like he's very well practiced at saying "sorry"

This is now the largest prime that i can keep in my head and write down :D

I suggest another challenge: Try looking for this last kind of prime where the base=n.

This is amazing!

Outrageous. Absolutely preposterous.

Counting down instead of up (eg 1110987654321) might lead to more primes as every term will end with 1

An interesting question would be the following: when we are testing for primes, just “counting upwards”, since they have now made it to 1000000, and he said it seems statistically likely that a prime should have shown up and it hasn’t, I would think it would be an interesting idea to try and figure out WHY you can’t hit a prime counting upwards in this fashion and maybe prove it true or false. What do you guys think?

“It gets harder as the numbers get bigger.”

I don't normally get into theoretical maths but I love this guy's energy.

For the 2nd part, I was wondering if this was true in other bases. I tried doing it for binary and came across a prime quite quickly, at 15 (1101110010111011110001001101010111100110111101111 = 485,098,038,695,407). I'm not sure if this means anything regarding the base 10 solution, but it does show that our arbitrary base number decision is making this more complicated than necessary!

Math, an endless playground.

Not nearly enough discussion is made about repunits (all 1's) as candidate primes. Worthy of more exploration!

What a delightful man. Would love to sit and listen to him ramble about mathematics over tea

I'm curious about other bases. Is it just a coincidence that the first one works for n=10 in base 10?

How on earth do they manage to prove that the 17,350-digit number is prime?

This is great. Problems that I can actually both understand and appreciate.

Cool that he gets to work in a Whataburger themed office.

What does the most want problem look like in other bases? Partial answer for base 2 n=15 (1111) Is prime (1101110010111011110001001101010111100110111101111) (485398038695407)

I wonder if the 1 .. 10 .. 1 prime works for every base you write the number in (like stopping when you reach the base). It seems to work for base 2 and 3

Great video!