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 A079684 #21 Nov 01 2022 13:47:54 %S A079684 0,0,0,0,0,0,0,0,1,1,1,1,0,0,0,2,0,1,2,1,1,0,0,1,5,3,2,1,3,3,2,1,7,2, %T A079684 3,7,4,5,1,5,3,5,3,9,3,5,1,5,7,6,6,6,4,9,8,5,3,4,5,8,8,4,8,5,9,7,7,6, %U A079684 9,10,5,7,8,6,10,7,11,7,9,10,8,8,15,10,13,8,10,13,8,12,10,6,18,12,12,15,9,12 %N A079684 Number of 3's in n!. %H A079684 Seiichi Manyama, <a href="/A079684/b079684.txt">Table of n, a(n) for n = 0..10000</a> %H A079684 <a href="/index/Fa#factorial">Index entries for sequences related to factorial numbers</a>. %F A079684 a(n) = A034886(n) - (A027869(n) + A079680(n) + A079714(n) + A079688(n) + A079690(n) + A079691(n) + A079692(n) + A079693(n) + A079694(n)). - _Reinhard Zumkeller_, Jan 27 2008 %t A079684 DigitCount[Range[0,100]!,10,3] (* _Harvey P. Dale_, Jul 04 2014 *) %Y A079684 Cf. A079714. %Y A079684 Cf. A000142, A137579, A137580. %K A079684 nonn,base,easy %O A079684 0,16 %A A079684 _Cino Hilliard_, Jan 31 2003 %E A079684 Corrected by _Jason Earls_, Jul 06 2003