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 A120535 #9 Jun 13 2016 19:36:26
%S A120535 4,9,21,26,33,38,55,65,77,111,142,159,166,183,205,217,226,265,346,371,
%T A120535 395,417,453,551,573,597,655,681,843,905,951,985,1059,1165,1441,1563,
%U A120535 2033,2073,2126,2361,2487,2841,2991,3831,4061,4601,8691,10911
%N A120535 Semiprimes that are not the sum of 3 pentagonal numbers.
%C A120535 Semiprime analog of A117065.
%t A120535 v = #*(3*#-1)/2& @ Range[0, 90]; Select[ Complement[ Range[0, 11000], Union[Total /@ Tuples[{v, v, v}]]], PrimeOmega[#] == 2 &] (* _Giovanni Resta_, Jun 13 2016 *)
%Y A120535 A001358 intersect A003679.
%Y A120535 Cf. A001358, A003679, A117065.
%K A120535 fini,full,nonn
%O A120535 1,1
%A A120535 _Jonathan Vos Post_, Aug 06 2006
%E A120535 Missing a(39) = 2126 from _Giovanni Resta_, Jun 13 2016