A090756 Numbers m of form 5k+1 such that binomial(m-1,(m-1)/5) == 1 (mod m).

11, 31, 41, 51, 61, 71, 101, 131, 141, 151, 181, 191, 211, 241, 251, 271, 281, 311, 321, 331, 401, 411, 421, 431, 461, 491, 521, 541, 571, 601, 631, 641, 661, 691, 701, 751, 761, 811, 821, 881, 911, 941, 951, 971, 991, 1021, 1031, 1051, 1061, 1091, 1151, 1171

Offset

1,1

Comments

Contains primes of form 5k+1 and some composite of form 5k+1 such that (5k+1)/3 is prime.

Links

Amiram Eldar, Table of n, a(n) for n = 1..10000

Mathematica

Select[5*Range[0, 250] + 1, Mod[Binomial[# - 1, (# - 1)/5] , #] == 1 &] (* Amiram Eldar, May 08 2022 *)

Crossrefs

Cf. A016861, A030430.

Sequence in context: A167488 A361976 A298566 * A038351 A068871 A004615

Adjacent sequences: A090753 A090754 A090755 * A090757 A090758 A090759

Keyword

nonn

Author

Benoit Cloitre, Feb 07 2004

Extensions

Offset corrected by Amiram Eldar, May 08 2022

Status

approved