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 A367506 #12 Nov 21 2023 08:31:37
%S A367506 2,25,280,6017,107776,3897218,107510656,4867995713,204519070720,
%T A367506 10904505179450,585061309782016,38168392129581810,2481946587976990720,
%U A367506 185404290282527361386,14389574562121084305408,1221867855128546542385409,108430221517525671050739712
%N A367506 a(n) = Sum_{d|n} (d+n)^n.
%F A367506 a(n) = Sum_{k=0..n} n^(n-k) * binomial(n,k) * sigma_k(n).
%o A367506 (PARI) a(n) = sumdiv(n, d, (d+n)^n);
%Y A367506 Cf. A163190, A163191, A367493, A367507, A367510.
%K A367506 nonn
%O A367506 1,1
%A A367506 _Seiichi Manyama_, Nov 21 2023