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 A039697 #26 Jun 09 2025 09:02:51 %S A039697 0,2,3,4,5,10,7,6,6,14,11,15,13,18,16,8,17,15,19,21,20,26,23,20,10,30, %T A039697 9,27,29,30,31,10,28,38,24,20,37,42,32,28,41,36,43,39,24,50,47,25,14, %U A039697 21,40,45,53,20,32,36,44,62,59,40,61,66,30,12,36,48,67,57,52,42,71,25 %N A039697 a(n) = Sum(p_j) * Sum(k_j) where n = Product(p_j^k_j). %H A039697 Seiichi Manyama, <a href="/A039697/b039697.txt">Table of n, a(n) for n = 1..10000</a> %F A039697 a(n) = A001222(n) * A008472(n). %e A039697 14 = 2^1 * 7^1, a(14) = (2+7)*(1+1) = 18. %t A039697 Array[If[# == 1, 0, Plus@@First/@FactorInteger[ # ]*Plus@@Last/@FactorInteger[ # ]]&, 5! ] (* _Vladimir Joseph Stephan Orlovsky_, Feb 28 2010 *) %o A039697 (PARI) a(n) = if(n == 1, 0, my(f = factor(n)); vecsum(f[,1]) * vecsum(f[,2])); \\ _Amiram Eldar_, Jun 09 2025 %Y A039697 Termwise product of A001222 and A008472. %K A039697 nonn,easy %O A039697 1,2 %A A039697 _Olivier Gérard_ %E A039697 a(1) corrected by _Amiram Eldar_, Jun 09 2025