OFFSET
1,1
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 1..1000
Tanya Khovanova, Recursive Sequences
Index entries for linear recurrences with constant coefficients, signature (3).
FORMULA
a(n) = 10*A008776(n+1).
G.f.: 20*x/(1-3*x). - Philippe Deléham, Nov 23 2008
From G. C. Greubel, Oct 31 2016: (Start)
a(n) = 20*3^(n-1).
E.g.f.: (20/3)*(exp(3*x) - 1). (End)
MATHEMATICA
Table[4*5*3^(n - 1), {n, 24}] (* Robert G. Wilson v, May 19 2006 *)
LinearRecurrence[{3}, {20}, 25] (* G. C. Greubel, Oct 31 2016 *)
PROG
(Magma) [20*3^(n-1): n in [1..30]]; // Vincenzo Librandi, Oct 31 2016
CROSSREFS
KEYWORD
nonn,less,easy
AUTHOR
Ben Gregson (mahishimi(AT)hotmail.com), Mar 26 2006
STATUS
approved