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A191549 Least number k such that kn + 1 is a prime dividing prime(n)^n - 1. 0

%I

%S 10,1,644,1,3663738,2,2,1,2,1,910,417,2,1,8,1,

%T 39547926178950768553863180373284,33,6,1,2,1943509,4,3,88,1,248,1,

%U 42284686073214306750946346164468593496471283975461929077356416,3,22896,1481424868782,1634,1,22260,1077,2,1

%N Least number k such that kn + 1 is a prime dividing prime(n)^n - 1.

%e a(3) = 10 because 10*3 + 1 = 31 and this number is the smallest prime divisor of the form kn+1

%e dividing prime(3)^3 - 1 = 5^3-1 = 124 = 2^2*31.

%t Table[p=First/@FactorInteger[Prime[ n]^n-1]; (Select[p, Mod[#1, n] == 1 &,

%t 1][[1]] - 1)/(n), {n, 3, 40}]

%Y Cf. A191548.

%K nonn

%O 3,1

%A _Michel Lagneau_, Jun 05 2011

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Last modified November 28 01:24 EST 2021. Contains 349396 sequences. (Running on oeis4.)