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%I #27 Aug 26 2019 05:05:43
%S 2,161038,6,12,10,30,14,56,18,30,22,132,26,182,30,48,34,306,38,380,42,
%T 66,46,552,50,130,54,84,58,870,62,992,66,102,70,180,74,1406,78,120,82,
%U 1722,86,1892,90,138,94,2256,98,350,102,156,106,2862,110,280,114,174,118,3540
%N Smallest k > n such that n divides k and n^k == n (mod k).
%H Amiram Eldar, <a href="/A271669/b271669.txt">Table of n, a(n) for n = 1..10000</a>
%F a(n) = 2n for odd n. - _Robert Israel_, Apr 12 2016
%F a(n) = n * A102457(n) for n > 1. - _Thomas Ordowski_, Apr 13 2016
%e 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
%t 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 *)
%o (PARI) a(n) = {k = n+1; while( !(((k % n)==0) && (Mod(n,k)^k == Mod(n, k))), k++); k;} \\ _Michel Marcus_, Apr 12 2016
%Y Cf. A006935, A102457.
%K nonn
%O 1,1
%A _Thomas Ordowski_, Apr 12 2016
%E More terms from _Michel Marcus_, Apr 12 2016