OFFSET
1,2
LINKS
Harry J. Smith, Table of n, a(n) for n = 1..100
Index entries for linear recurrences with constant coefficients, signature (40,-400).
FORMULA
G.f.: x /(1 - 20*x)^2. - Vincenzo Librandi, Jul 02 2018
a(n) = n*20^(n-1).
MATHEMATICA
CoefficientList[Series[(1)/(1 - 20 x)^2, {x, 0, 20}], x] (* Vincenzo Librandi, Jul 02 2018 *)
LinearRecurrence[{40, -400}, {1, 40}, 20] (* Harvey P. Dale, Aug 01 2021 *)
PROG
(PARI) { for (n=1, 100, write("b061650.txt", n, " ", n*20^(n - 1)) ) } \\ Harry J. Smith, Jul 25 2009
(Magma) [n*20^(n-1): n in [1..20]]; // Vincenzo Librandi, Jul 02 2018
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Jason Earls, Jun 14 2001
EXTENSIONS
Corrected and extended by Larry Reeves (larryr(AT)acm.org), Jun 18 2001
STATUS
approved