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 A091296 #27 Jul 08 2025 13:56:10
%S A091296 9,15,33,35,39,51,55,57,77,91,93,95,111,115,119,133,155,159,177,319,
%T A091296 335,339,355,371,377,391,393,395,511,515,517,519,533,535,537,551,553,
%U A091296 559,573,579,591,597,713,717,731,737,753,755,771,779,791,793,799,913,917
%N A091296 Semiprimes with odd digits.
%C A091296 Semiprimes with odd digits are more numerous than those with even digits, cf. A108636.
%H A091296 Mia Boudreau, <a href="/A091296/b091296.txt">Table of n, a(n) for n = 1..1000</a>
%t A091296 Select[Range[1000], Plus@@Last/@FactorInteger[ # ]==2&&Union[OddQ/@IntegerDigits[ # ]]=={True}&]
%t A091296 PrimeFactorExponentsAdded[n_] := Plus @@ Flatten[ Table[ #[[2]], {1}] & /@ FactorInteger[n]]; Select[ Range[ 938], PrimeFactorExponentsAdded[ # ] == 2 && Union[ OddQ /@ IntegerDigits[ # ]] == {True} &] (* _Robert G. Wilson v_, Feb 25 2004 *)
%t A091296 Select[Range[1000], PrimeOmega[#]==2 && And@@OddQ[IntegerDigits[#]]&] (* _Harvey P. Dale_, Jul 12 2011 *)
%Y A091296 Intersection of A001358 and A014261.
%Y A091296 Cf. A030096, A108636.
%K A091296 easy,nonn,base
%O A091296 1,1
%A A091296 _Zak Seidov_, Feb 22 2004
%E A091296 Corrected and extended by _Ray Chandler_ and _Robert G. Wilson v_, Feb 25 2004
%E A091296 Edited by _N. J. A. Sloane_, Apr 20 2007