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 A112370 #9 Dec 30 2023 08:14:27
%S A112370 1,4,22,184,2128,31288,556168,11578648,276118168,7418685208,
%T A112370 221695696408,7292837066008,261853926371608,10189736409290008,
%U A112370 427160800691862808,19190858693407638808,919848357543764886808,46853380798911984534808,2527264132632795845526808
%N A112370 a(n) = Sum_{i=0..n} 3^i*i!.
%H A112370 Seiichi Manyama, <a href="/A112370/b112370.txt">Table of n, a(n) for n = 0..380</a>
%t A112370 Accumulate[Table[3^i (i!),{i,0,20}]] (* _Harvey P. Dale_, Feb 21 2013 *)
%Y A112370 Cf. A112368.
%K A112370 nonn
%O A112370 0,2
%A A112370 _N. J. A. Sloane_, Dec 02 2005