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.

A234003 Prime(n), where n is such that (1+Sum_{i=1..n} prime(i)^5) / n is an integer.

Original entry on oeis.org

2, 3, 7, 13, 29, 37, 79, 271, 907, 2447, 3301, 4969, 9241, 26111, 27941, 38039, 58603, 90071, 243469, 617579, 849143, 6994363, 10661177, 68783413, 122137849, 131221879, 187987693, 194658539, 283102597, 329015387, 1682202323, 5230637117, 5461627177, 32315983207, 69900989237, 154638658121, 227225999443, 306462968363, 349585319959, 1128669425707, 1245067407509
Offset: 1

Views

Author

Robert Price, Dec 18 2013

Keywords

Comments

a(52) > 1005368767096627. - Bruce Garner, Jun 05 2021
a(53) > 4193009611262897. - Bruce Garner, Mar 28 2022

Examples

			a(4) = 13, because 13 is the 6th prime and the sum of the first 6 primes^5 + 1 = 552552 when divided by 6 equals 92092 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 = 1; Do[sm = sm + Prime[n]^5; 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)^5); s==0 \\ Charles R Greathouse IV, Nov 30 2013