OFFSET
1,2
COMMENTS
E.g.f. is g.f. for A011557(n-1) (powers of ten).
LINKS
FORMULA
10*a(n) = (10*n)(!^10) = Product_{j=1..n} 10*j = 10^n*n!.
E.g.f.: (-1 + (1-10*x)^(-1))/10.
From Amiram Eldar, Jan 08 2022: (Start)
Sum_{n>=1} 1/a(n) = 10*(exp(1/10)-1).
Sum_{n>=1} (-1)^(n+1)/a(n) = 10*(1-exp(-1/10)). (End)
MAPLE
seq(10^(n-1)*n!, n=1..20); # G. C. Greubel, Nov 11 2019
MATHEMATICA
Table[10^(n-1)*n!, {n, 20}] (* G. C. Greubel, Nov 11 2019 *)
PROG
(PARI) vector(20, n, 10^(n-1)*n! ) \\ G. C. Greubel, Nov 11 2019
(Magma) [10^(n-1)*Factorial(n): n in [1..20]]; // G. C. Greubel, Nov 11 2019
(Sage) [10^(n-1)*factorial(n) for n in (1..20)] # G. C. Greubel, Nov 11 2019
(GAP) List([1..20], n-> 10^(n-1)*Factorial(n) ); # G. C. Greubel, Nov 11 2019
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
STATUS
approved