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 A035279 #27 Sep 08 2022 08:44:52
%S A035279 1,20,600,24000,1200000,72000000,5040000000,403200000000,
%T A035279 36288000000000,3628800000000000,399168000000000000,
%U A035279 47900160000000000000,6227020800000000000000,871782912000000000000000,130767436800000000000000000,20922789888000000000000000000
%N A035279 One tenth of deca-factorial numbers.
%C A035279 E.g.f. is g.f. for A011557(n-1) (powers of ten).
%H A035279 G. C. Greubel, <a href="/A035279/b035279.txt">Table of n, a(n) for n = 1..320</a>
%H A035279 <a href="/index/Fa#factorial">Index entries for sequences related to factorial numbers</a>.
%F A035279 10*a(n) = (10*n)(!^10) = Product_{j=1..n} 10*j = 10^n*n!.
%F A035279 E.g.f.: (-1 + (1-10*x)^(-1))/10.
%F A035279 From _Amiram Eldar_, Jan 08 2022: (Start)
%F A035279 Sum_{n>=1} 1/a(n) = 10*(exp(1/10)-1).
%F A035279 Sum_{n>=1} (-1)^(n+1)/a(n) = 10*(1-exp(-1/10)). (End)
%p A035279 seq(10^(n-1)*n!, n=1..20); # _G. C. Greubel_, Nov 11 2019
%t A035279 Table[10^(n-1)*n!, {n,20}] (* _G. C. Greubel_, Nov 11 2019 *)
%o A035279 (PARI) vector(20, n, 10^(n-1)*n! ) \\ _G. C. Greubel_, Nov 11 2019
%o A035279 (Magma) [10^(n-1)*Factorial(n): n in [1..20]]; // _G. C. Greubel_, Nov 11 2019
%o A035279 (Sage) [10^(n-1)*factorial(n) for n in (1..20)] # _G. C. Greubel_, Nov 11 2019
%o A035279 (GAP) List([1..20], n-> 10^(n-1)*Factorial(n) ); # _G. C. Greubel_, Nov 11 2019
%Y A035279 Cf. A011557, A045757.
%K A035279 easy,nonn
%O A035279 1,2
%A A035279 _Wolfdieter Lang_