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%I #20 May 07 2021 20:34:10
%S 1,2,3,4,5,6,8,12,15,19,24,95,361,876
%N Numbers k such that k^2 divides 5^k - 3^k - 2^k.
%C Are there only finitely many such numbers?
%C Primes in the sequence are A130076.
%C Next term, if it exists, exceeds 5*10^8. - _Jon E. Schoenfield_, May 07 2021
%p q:= k-> is(0=5&^k-3&^k-2&^k mod k^2):
%p select(q, [$1..1000])[]; # _Alois P. Heinz_, May 07 2021
%t Select[Range[1000], Mod[PowerMod[2, #, #^2] + PowerMod[3, #, #^2],#^2] == PowerMod[5, #, #^2] &] (* _Amiram Eldar_, Apr 05 2021 *)
%Y Cf. A130072, A130073, A130076.
%K nonn,more
%O 1,2
%A _Thomas Ordowski_, Apr 05 2021