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%I #12 May 11 2019 17:54:06
%S 0,22,86,154,160,488,705,958,975,1262,1932,2845,12718,14434,20337,
%T 38834,40433,44874
%N Numbers k such that binomial(5k, k) + 1 is prime.
%C a(19) > 50000. - _Robert Price_, May 11 2019
%t Do[f=Binomial[5n, n]+1; If[PrimeQ[f], Print[n]], {n, 1, 1000}]
%Y Cf. A125242 = numbers n such that binomial(5n, n) - 1 is prime. Cf. A066699 = numbers n such that binomial(2n, n) + 1 is prime. Cf. A066726 = numbers n such that binomial(2n, n) - 1 is prime. Cf. A125220, A125221, A125240, A125241, A125244, A125245.
%K hard,more,nonn
%O 1,2
%A _Alexander Adamchuk_, Nov 25 2006
%E More terms from _Ryan Propper_, Jan 05 2007
%E a(1)=0 prepended and a(13)-a(18) added by _Robert Price_, May 11 2019