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%I #8 May 13 2019 21:30:39
%S 0,1,2,4,10,15,98,111,118,236,280,512,1284,1303,1818,2525,2692,4620,
%T 8405,11539,13190,21525,30338,48069
%N Numbers k such that binomial(6k, k) + 1 is prime.
%C a(25) > 50000. - _Robert Price_, May 13 2019
%t Do[f=Binomial[6n, n]+1; If[PrimeQ[f], Print[n]], {n, 1, 1000}]
%Y Cf. A125244 = numbers n such that binomial(6n, 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, A125242, A125243.
%K hard,more,nonn
%O 1,3
%A _Alexander Adamchuk_, Nov 25 2006
%E More terms from _Ryan Propper_, Mar 28 2007
%E a(1)=0 and a(20)-a(24) from _Robert Price_, May 13 2019