A074485 Bases k for which the smallest (Fermat) pseudoprime greater than k has Moebius function mu = -1.

41, 49, 71, 83, 97, 104, 111, 148, 155, 157, 161, 163, 164, 167, 169, 181, 190, 194, 197, 205, 209, 223, 227, 229, 230, 231, 239, 243, 254, 265, 269, 272, 277, 284, 323, 331, 341, 344, 348, 351, 353, 355, 356, 358, 371, 373, 379, 383, 384, 388, 391, 395

Offset: 1

Author

Jani Melik, Sep 25 2002

Keywords

• easy
• nonn

Examples

			41: Its smallest pseudoprime is 105 = 3 * 5 * 7 and mu (105) = -1 <= (105 > 41).
49: Its smallest pseudoprime is 66 = 2 * 3 * 11 and mu (66) = -1 <= (66 > 49).
71: Its smallest pseudoprime is 105 = 3 * 5 * 7 and mu (105) = -1 <= (105 > 71).
		

Links

• Charles R Greathouse IV, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A007535, A008683, A074228.

Programs

Mathematica

q[n_] := Module[{k = n + 1}, While[! CoprimeQ[n, k] || PrimeQ[k] || PowerMod[n, k - 1, k] != 1, k++]; MoebiusMu[k] == -1]; Select[Range[400], q] (* Amiram Eldar, Mar 31 2024 *)

PARI

is(n)=my(k=n+1);while(isprime(k)||Mod(n,k)^(k-1)!=1,k++);moebius(k)<0 \\ Charles R Greathouse IV, Aug 22 2013