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 A367255 #8 Dec 01 2023 04:40:27
%S A367255 1,2,7,40,325,3456,45619,720896,13286025,280000000,6645125311,
%T A367255 175432531968,5100764198413,161982606786560,5579092529296875,
%U A367255 207165582859042816,8250513501410645521,350825312056827838464,15864277746219164222455,760217600000000000000000
%N A367255 a(n) = (n + 1)^(n - 2)*(3*n + 1).
%F A367255 a(n) = Sum_{k=0..n} binomial(n - 1, k - 1) * n^(n - k) * (k + 1). (See A137452.)
%p A367255 a := n -> (n + 1)^(n - 2)*(3*n + 1): seq(a(n), n = 0..19);
%t A367255 A367255[n_]:=(n+1)^(n-2)(3n+1);
%t A367255 Array[A367255,25,0] (* _Paolo Xausa_, Dec 01 2023 *)
%Y A367255 Cf. A137452.
%K A367255 nonn
%O A367255 0,2
%A A367255 _Peter Luschny_, Nov 11 2023