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 A351895 #10 Feb 26 2022 10:11:07 %S A351895 2,5,25,26,29,30,34,37,38,41,42,46,51,55,56,59,63,67,68,71,73,74,77, %T A351895 78,82,85,86,89,90,94,99,103,104,107,111,115,116,119,723,727,728,731, %U A351895 735,739,740,743,745,746,749,750,754,757,758,761,762,766,771,775,776 %N A351895 Numbers with an equal number of odd and even digits in their factorial-base representation. %H A351895 Amiram Eldar, <a href="/A351895/b351895.txt">Table of n, a(n) for n = 1..10000</a> %H A351895 Wikipedia, <a href="https://en.wikipedia.org/wiki/Factorial_number_system">Factorial number system</a>. %H A351895 <a href="/index/Fa#facbase">Index entries for sequences related to factorial base representation</a>. %e A351895 5 is a term since its factorial-base representation, 21, has one odd digit, 1, and one even digit, 2. %t A351895 max = 7; fctBaseDigits[n_] := IntegerDigits[n, MixedRadix[Range[max, 2, -1]]]; Select[Range[1, max!], EvenQ[Length[(d = fctBaseDigits[#])]] && Count[d, _?EvenQ] == Length[d]/2 &] %Y A351895 Cf. A007623, A351893, A351894. %Y A351895 A138524 is a subsequence. %Y A351895 Similar sequences: A031443 (binary), A227870 (decimal). %K A351895 nonn,base %O A351895 1,1 %A A351895 _Amiram Eldar_, Feb 24 2022