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A267298 Integers k such that the k-th prime divides the product of the first k nonzero Jacobsthal numbers.

%I A267298 #14 Jul 20 2019 01:05:00
%S A267298 5,11,14,21,24,30,31,36,53,54,55,60,61,63,67,68,78,84,88,95,105,110,
%T A267298 113,115,116,117,122,124,125,131,141,152,162,164,170,174,176,177,184,
%U A267298 185,192,196,199,204,216,226,234,245,255,260,267,273,275,279,280,304,305,316,319,324,339,349,356,358,366
%N A267298 Integers k such that the k-th prime divides the product of the first k nonzero Jacobsthal numbers.
%C A267298 If any A001045(j) has a prime divisor p where p is the k-th prime for 1 <= j <= k, then k is a term of this sequence.
%e A267298 5 is a term because A001045(5) = 11 is divisible by 11.
%o A267298 (PARI) a001045(n) = (2^n - (-1)^n) / 3;
%o A267298 lista(nn) = for(n=1, nn, my(p = prime(n)); if (lift(prod(i=1, n, Mod(a001045(i), p))) == 0, print1(n, ", ")));
%Y A267298 Cf. A001045, A269694.
%K A267298 nonn
%O A267298 1,1
%A A267298 _Altug Alkan_, Apr 07 2016