This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A120536 #5 Jun 13 2016 09:40:45
%S A120536 215,381,447,766,807,1457,1622,1639,1927,2047,2245,2302,2497,3027,
%T A120536 3173,3437,3715,3787,4359,4369,4577,4594,4677,4681,5029,5277,5377,
%U A120536 5435,5617,5747,5911,6065,6117,6537,6711,6722,6782,7087,7157,7327,7538,7661,7813,7827
%N A120536 Semiprimes which are the sum of two pentagonal numbers (A000326) in exactly two different ways.
%C A120536 Semiprimes in A064826 Numbers which are the sum of two pentagonal numbers (A000326) in exactly two different ways.
%t A120536 T = Range[10^4]*0; q = # (3 # - 1)/2 &@ Range[81]; Do[ s = q[[i]] + q[[j]]; If[s <= 10^4, T[[s]]++], {i, Length[q]}, {j, i}]; Select[ Flatten@ Position[T, 2], PrimeOmega[#] == 2 &] (* _Giovanni Resta_, Jun 13 2016 *)
%Y A120536 A001358 intersect A064826.
%Y A120536 Cf. A000326, A001358, A064826.
%K A120536 nonn
%O A120536 1,1
%A A120536 _Jonathan Vos Post_, Aug 06 2006
%E A120536 a(14)-a(44) from _Giovanni Resta_, Jun 13 2016