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 A258645 #4 Jun 07 2015 07:24:13 %S A258645 0,0,0,0,4,0,0,0,176,0,0,0,368,0,0,80,752,0,0,0,240,0,0,0,608,0,32,27, %T A258645 752,0,0,0,1520,1,0,176,560,0,0,368,284,0,0,0,1552,176,0,0,3120,1,80, %U A258645 112,560,0,1188,368,1312,0,0,0,1312,0,5,48,36864,1,0,0 %N A258645 Fifth arithmetic derivative of n. %H A258645 Alois P. Heinz, <a href="/A258645/b258645.txt">Table of n, a(n) for n = 0..10000</a> %F A258645 a(n) = A003415^5(n). %p A258645 d:= n-> n*add(i[2]/i[1], i=ifactors(n)[2]): %p A258645 A:= proc(n, k) option remember; `if`(k=0, n, d(A(n, k-1))) end: %p A258645 a:= n-> A(n, 5): %p A258645 seq(a(n), n=0..70); %Y A258645 Column k=5 of A258651. %Y A258645 Cf. A003415. %K A258645 nonn %O A258645 0,5 %A A258645 _Alois P. Heinz_, Jun 06 2015