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A073943
a(n) = smallest m such that n-th prime divides m^m + 1.
1
1, 5, 2, 3, 21, 6, 24, 27, 11, 14, 15, 6, 25, 63, 23, 26, 117, 30, 99, 35, 9, 39, 165, 11, 6, 10, 51, 213, 54, 7, 63, 261, 174, 23, 74, 33, 78, 27, 83, 86, 357, 30, 95, 12, 14, 11, 15, 111, 453, 18, 12, 119, 90, 501, 4, 131, 82, 135, 117, 60, 45, 138, 51, 95, 54, 114, 75
OFFSET
1,2
LINKS
EXAMPLE
6th prime is 13 and 13 first divides 6^6 + 1 = 46657, so a(6) = 6.
MATHEMATICA
smp[n_]:=Module[{m=1}, While[PowerMod[m, m, n]!=n-1, m++]; m]; smp/@Prime[ Range[ 70]] (* Harvey P. Dale, Jul 21 2018 *)
CROSSREFS
Cf. A014566.
Sequence in context: A105269 A248262 A291690 * A193797 A350518 A214662
KEYWORD
easy,nonn
AUTHOR
Jason Earls, Nov 13 2002
STATUS
approved