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

10, 1, 644, 1, 3663738, 2, 2, 1, 2, 1, 910, 417, 2, 1, 8, 1, 39547926178950768553863180373284, 33, 6, 1, 2, 1943509, 4, 3, 88, 1, 248, 1, 42284686073214306750946346164468593496471283975461929077356416, 3, 22896, 1481424868782, 1634, 1, 22260, 1077, 2, 1

Offset

3,1

Links

Table of n, a(n) for n=3..40.

Example

a(3) = 10 because 10*3 + 1 = 31 and this number is the smallest prime divisor of the form kn+1
  dividing prime(3)^3 - 1 = 5^3-1 = 124 = 2^2*31.

Mathematica

Table[p=First/@FactorInteger[Prime[ n]^n-1]; (Select[p, Mod[#1, n] == 1 &,
  1][[1]] - 1)/(n), {n, 3, 40}]

Crossrefs

Cf. A191548.

Sequence in context: A048176 A127616 A277394 * A285647 A287975 A288365

Adjacent sequences: A191546 A191547 A191548 * A191550 A191551 A191552

Keyword

nonn

Author

Michel Lagneau, Jun 05 2011

Status

approved