cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A233192 Prime(k), where k is such that (Sum_{j=1..k} prime(j)^11) / k is an integer.

Original entry on oeis.org

2, 97, 277, 23311, 61583, 6133811, 210952097, 359643241, 5451597181, 42641466149, 51575229001, 199655689679, 248181386429, 61646670874849, 82153230089767, 212374157550341, 11432141933990629, 15031011453909223
Offset: 1

Views

Author

Robert Price, Dec 05 2013

Keywords

Comments

a(17) > 257180056649941. - Bruce Garner, Mar 29 2021
a(19) > 18205684894350047. - Paul W. Dyson, Jan 16 2025

Examples

			a(2) = 97, because 97 is the 25th prime and the sum of the first 25 primes^11 = 12718098700540100969050 when divided by 25 equals 508723948021604038762 which is an integer.
		

Crossrefs

Cf. A085450 = smallest m > 1 such that m divides Sum_{k=1..m} prime(k)^n.

Programs

  • Mathematica
    t = {}; sm = 0; Do[sm = sm + Prime[n]^11; If[Mod[sm, n] == 0, AppendTo[t, Prime[n]]], {n, 100000}]; t (* Derived from A217599 *)
  • PARI
    is(n)=if(!isprime(n),return(0)); my(t=primepi(n),s); forprime(p=2,n,s+=Mod(p,t)^11); s==0 \\ Charles R Greathouse IV, Nov 30 2013
    
  • PARI
    S=n=0;forprime(p=1,,(S+=p^11)%n++||print1(p",")) \\ M. F. Hasler, Dec 01 2013

Formula

a(n) = prime(A125827(n)).

Extensions

a(14) from Paul W. Dyson, Jan 08 2021
a(15) from Bruce Garner, Mar 08 2021
a(16) from Bruce Garner, Mar 29 2021
a(17) from Paul W. Dyson, Jan 03 2023
a(18) from Paul W. Dyson, Dec 20 2024