%I
%S 0,1,2,3,4,5,6,10,11,13,15,15,18,22,24,25,29,31,33,37,45,55,
%T 55,59,67,72,74,80,81,85,86,88,90,95,99,101,102,108,116,118,
%U 122,129,130,143,148,151,155,157,158,159,162,164,165
%N Numbers k such that 36*k^2 + 12*k + 7 is prime (sorted by absolute values with negatives before positives).
%C 36*k^2 + 12*k + 7 = (6*k+1)^2 + 6, which is six more than a square.
%F a(n) = (1 + sqrt(A056909(n)  6))/6, choosing + to give an integer result for each n.
%e a(2)=2 since 36*(2)^2 + 12*(2) + 7 = 127, which is prime (as well as being six more than a square).
%Y This sequence and formula generate all primes of the form k^2+6, i.e., A056909. Except for the first term, none of the a(n) are a multiple of 7 and so the rest of this sequence is a subsequence of A047304. Cf. A056900, A056902, A056904, A056906, A056907, A056908.
%K sign
%O 0,3
%A _Henry Bottomley_, Jul 07 2000
