A246392 Numbers n such that Phi(10, n) is prime, where Phi is the cyclotomic polynomial.

2, 3, 5, 10, 11, 12, 16, 20, 21, 22, 33, 37, 38, 43, 47, 48, 55, 71, 75, 76, 80, 81, 111, 121, 126, 131, 133, 135, 136, 141, 155, 157, 158, 165, 176, 177, 180, 203, 223, 242, 245, 251, 253, 256, 257, 258, 265, 268, 276, 286, 290, 297, 307, 322, 323, 342, 361, 363, 366, 375, 377, 385, 388, 396, 411

Offset

1,1

Comments

Numbers n such that (n^5+1)/(n+1) is prime, or numbers n such that A060884(n) is prime.

Links

Ray Chandler, Table of n, a(n) for n = 1..10000 (first 893 terms from Robert Price)

OEIS Wiki, Cyclotomic Polynomials at x=sigma(n)

Maple

A246392:=n->`if`(isprime((n^5+1)/(n+1)), n, NULL): seq(A246392(n), n=1..500); # Wesley Ivan Hurt, Nov 15 2014

Mathematica

Select[Range[700], PrimeQ[(#^5 + 1) / (# + 1)] &] (* Vincenzo Librandi, Nov 14 2014 *)

Prog

(PARI) for(n=1, 10^3, if(isprime(polcyclo(10, n)), print1(n, ", "))); \\ Joerg Arndt, Nov 13 2014
(Magma) [n: n in [1..500]| IsPrime((n^5+1) div (n+1))]; // Vincenzo Librandi, Nov 14 2014

Crossrefs

Cf. A008864 (1), A006093 (2), A002384 (3), A005574 (4), A049409 (5), A055494 (6), A100330 (7), A000068 (8), A153439 (9), this sequence (10), A162862 (11), A246397 (12), A217070 (13), A006314 (16), A217071 (17), A164989 (18), A217072 (19), A217073 (23), A153440 (27), A217074 (29), A217075 (31), A006313 (32), A097475 (36), A217076 (37), A217077 (41), A217078 (43), A217079 (47), A217080 (53), A217081 (59), A217082 (61), A006315 (64), A217083 (67), A217084 (71), A217085 (73), A217086 (79), A153441 (81), A217087 (83), A217088 (89), A217089 (97), A006316 (128), A153442 (243), A056994 (256), A056995 (512), A057465 (1024), A057002 (2048), A088361 (4096), A088362 (8192), A226528 (16384), A226529 (32768), A226530 (65536).

Cf. A060884, A085398, A259257.

Sequence in context: A094542 A175481 A288244 * A219860 A076681 A047604

Adjacent sequences: A246389 A246390 A246391 * A246393 A246394 A246395

Keyword

nonn

Author

Eric Chen, Nov 13 2014

Status

approved