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%I #9 Apr 21 2019 15:17:31
%S 2,3,7,11,13,29,31,37,43,61,67,73,79,83,97,101,127,137,139,151,157,
%T 163,181,191,193,199,211,227,241,263,277,281,307,331,353,367,373,379,
%U 389,409,421,433,443,461,463,487,499,541,571,577,587,601,619,631,659,661
%N Primes expressible as the sum of two triangular numbers (including zero).
%C See A117048 for the primes that are the sum of two positive triangular numbers. The only difference is that the prime 3 occurs here.
%F A000040 intersect A020756. - _Jonathan Vos Post_, Apr 17 2006
%e 2 = 1 + 1
%e 3 = 0 + 3
%e 7 = 1 + 6
%e and so on.
%t tri = Table[n (n + 1)/2, {n, 0, 40}]; Select[Union[Flatten[Outer[Plus, tri, tri]]], # <= tri[[-1]]+1 && PrimeQ[#] &] (* _T. D. Noe_, Apr 07 2011 *)
%t Select[Total/@Tuples[Accumulate[Range[0,40]],2],PrimeQ]//Union (* _Harvey P. Dale_, Apr 21 2019 *)
%Y Cf. A000217, A117048.
%K easy,nonn
%O 1,1
%A _Greg Huber_, Apr 18 2006
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