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 A175091 #10 Feb 11 2021 01:20:27
%S A175091 4,7,13,15,21,22,23,24,40,49,50,51,52,53,54,57,64,65,66,67,68,73,74,
%T A175091 79,80,94,95,96,99,100,101,102,111,112,122,123,124,127,134,135,136,
%U A175091 137,138,145,146,147,148,149,150,159,160,172,173,174,177,178,179,180,181,182
%N A175091 Numbers k such that A074753(k) == (2,4) (mod 6).
%p A175091 A074753 := proc(n) option remember ; local a,k ; a := 0 ; for k from 1 to n do if numtheory[sigma](k) < n then a := a+1 ; end if; end do ; a ; end proc: isA175091 := proc(n) return ( (A074753(n) mod 6 )in {2,4}) ; end proc ; for n from 1 to 300 do if isA175091(n) then printf("%d,",n) ; end if; end do ; # _R. J. Mathar_, Feb 08 2010
%Y A175091 Cf. A074753.
%K A175091 nonn
%O A175091 1,1
%A A175091 _Giovanni Teofilatto_, Jan 29 2010
%E A175091 Corrected by _R. J. Mathar_, Feb 08 2010