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 A258650 #11 Nov 03 2022 11:24:45 %S A258650 0,0,0,0,4,0,0,0,8592,0,0,0,20096,0,0,3424,70464,0,0,0,16304,0,0,0, %T A258650 32624,0,1520,27,70464,0,0,0,235072,0,0,8592,47872,0,0,20096,24640,0, %U A258650 0,0,65264,8592,0,0,130544,0,3424,8144,47872,0,57996,20096,198656,0,0 %N A258650 Tenth arithmetic derivative of n. %H A258650 Alois P. Heinz, <a href="/A258650/b258650.txt">Table of n, a(n) for n = 0..10000</a> %F A258650 a(n) = A003415^10(n). %p A258650 d:= n-> n*add(i[2]/i[1], i=ifactors(n)[2]): %p A258650 A:= proc(n, k) option remember; `if`(k=0, n, d(A(n, k-1))) end: %p A258650 a:= n-> A(n, 10): %p A258650 seq(a(n), n=0..70); %o A258650 (Python) %o A258650 from sympy import factorint %o A258650 def A258650(n): %o A258650 for _ in range(10): %o A258650 if n <= 1: return 0 %o A258650 n = sum((n*e//p for p,e in factorint(n).items())) %o A258650 return n # _Chai Wah Wu_, Nov 03 2022 %Y A258650 Column k=10 of A258651. %Y A258650 Cf. A003415. %K A258650 nonn %O A258650 0,5 %A A258650 _Alois P. Heinz_, Jun 06 2015