A207837 Primes of the form 5*k^4 + 1.

6481, 103681, 844480081, 1036800001, 55099802881, 63727534081, 115672050001, 155584800001, 307529920081, 322620641281, 425152800001, 1019640545281, 1633266996481, 1739461754881, 2489356800001, 2634683086081, 2944329626881, 5285935072081, 6360160441681

Offset

1,1

Comments

Also primes of the form 6480*k^4+1.

Links

Vincenzo Librandi, Table of n, a(n) for n = 1..1500

Formula

a(n) = 5*A207838(n)^4 + 1. - Paul F. Marrero Romero, Dec 07 2023

Mathematica

Select[5 Range[1086]^4 + 1, PrimeQ] (* by definition *)

Prog

(PARI) for(n=1, 181, r=6480*n^4+1; if(isprime(r), print1(r", ")));
(Magma) [6480*n^4+1: n in [1..181] | IsPrime(6480*n^4+1)];

Crossrefs

Cf. A207838 (values of k).

Subsequence of A137530.

Primes of the form k*n^(k-1)+1: A065091, A002648, A199307.

Sequence in context: A362878 A087351 A104343 * A104242 A031842 A028544

Adjacent sequences: A207834 A207835 A207836 * A207838 A207839 A207840

Keyword

nonn,easy

Author

Bruno Berselli, Feb 21 2012

Status

approved