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A271669
Smallest k > n such that n divides k and n^k == n (mod k).
1
2, 161038, 6, 12, 10, 30, 14, 56, 18, 30, 22, 132, 26, 182, 30, 48, 34, 306, 38, 380, 42, 66, 46, 552, 50, 130, 54, 84, 58, 870, 62, 992, 66, 102, 70, 180, 74, 1406, 78, 120, 82, 1722, 86, 1892, 90, 138, 94, 2256, 98, 350, 102, 156, 106, 2862, 110, 280, 114, 174, 118, 3540
OFFSET
1,1
LINKS
FORMULA
a(n) = 2n for odd n. - Robert Israel, Apr 12 2016
a(n) = n * A102457(n) for n > 1. - Thomas Ordowski, Apr 13 2016
EXAMPLE
Because of the definition of (pseudo)primes to base 2, a(2) is the least element of A006935 greater than 2. - Altug Alkan, Apr 12 2016
MATHEMATICA
Table[SelectFirst[Range[n + 1, 10^6], Function[k, Divisible[k, n] && PowerMod[n, k, k] == Mod[n, k]]], {n, 60}] (* Michael De Vlieger, Apr 12 2016, Version 10 *)
PROG
(PARI) a(n) = {k = n+1; while( !(((k % n)==0) && (Mod(n, k)^k == Mod(n, k))), k++); k; } \\ Michel Marcus, Apr 12 2016
CROSSREFS
Sequence in context: A324438 A167518 A178168 * A006935 A070833 A176584
KEYWORD
nonn
AUTHOR
Thomas Ordowski, Apr 12 2016
EXTENSIONS
More terms from Michel Marcus, Apr 12 2016
STATUS
approved