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 A331051 #6 Jan 11 2020 15:27:27
%S A331051 4,6,9,10,12,14,15,18,20,21,22,25,26,28,33,34,35,38,39,44,45,46,48,49,
%T A331051 50,51,52,55,57,58,62,63,65,68,69,72,74,75,76,77,80,82,85,86,87,91,92,
%U A331051 93,94,95,98,99,106,108,111,112,115,116,117,118,119,121,122
%N A331051 Numbers whose number of factorizations into factors > 1 (A001055) is even.
%C A331051 First differs from A319240 in having 256.
%t A331051 facs[n_]:=If[n<=1,{{}},Join@@Table[Map[Prepend[#,d]&,Select[facs[n/d],Min@@#>=d&]],{d,Rest[Divisors[n]]}]];
%t A331051 Select[Range[300],EvenQ[Length[facs[#]]]&]
%Y A331051 Complement of A331050.
%Y A331051 The version for powers of two (instead of evens) is A330977.
%Y A331051 The version for primes (instead of evens) is A330991.
%Y A331051 Cf. A001055, A001221, A001222, A002033, A005117, A045778, A045782, A045783, A330972, A330973.
%K A331051 nonn
%O A331051 1,1
%A A331051 _Gus Wiseman_, Jan 10 2020