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 A330572 #25 Apr 19 2024 03:30:00
%S A330572 0,1,2,3,6,7,10,12,14,19,20,24,28,31,32,40,40,48,48,56,56,67,60,77,72,
%T A330572 85,80,98,88,108,98,117,110,131,110,147,128,149,140,169,144,182,154,
%U A330572 192,174,205,168,228,188,226,208,250,204,268,218,273,246,285,234,324
%N A330572 a(n) = Sum_{k = 1..n} [u_2(k)*u_2(n+1-k)], where u_2(k) is the number of unordered factorizations k = i*j (A038548).
%C A330572 An analog of A055507 for unordered factorizations.
%C A330572 For background references see A330570.
%H A330572 Robert Israel, <a href="/A330572/b330572.txt">Table of n, a(n) for n = 0..10000</a>
%p A330572 u2:= proc(n) option remember; if issqr(n) then (numtheory:-tau(n)+1)/2 else numtheory:-tau(n)/2 fi end proc:
%p A330572 f:= proc(n) local k; add(u2(k)*u2(n+1-k),k=1..n) end proc:
%p A330572 map(f, [$0..100]); # _Robert Israel_, Dec 05 2022
%t A330572 s[n_] := s[n] = Ceiling[DivisorSigma[0, n] / 2]; a[n_] := Sum[s[k] * s[n+1-k], {k, 1, n}]; Array[a, 100, 0] (* _Amiram Eldar_, Apr 19 2024 *)
%Y A330572 Cf. A000005, A038548, A055507.
%Y A330572 See A330573 for another version.
%K A330572 nonn,look
%O A330572 0,3
%A A330572 _N. J. A. Sloane_, Jan 08 2020
%E A330572 Offset corrected by _Robert Israel_, Dec 05 2022