OFFSET
0,2
COMMENTS
n-th difference of a(n), a(n-1), ..., a(0) is 6^(n-1) for n=1, 2, 3, ...
LINKS
FORMULA
a(n) = (7^n + 5)/6. - Ralf Stephan, Feb 14 2004
From Philippe Deléham, Oct 06 2009: (Start)
a(0) = 1, a(1) = 2, a(n) = 8*a(n-1) - 7*a(n-2) for n > 1.
G.f.: (1 - 6*x)/(1 - 8*x + 7*x^2). (End)
a(n) = 7*a(n-1) - 5, with a(0)=1. - Vincenzo Librandi, Aug 06 2010
E.g.f.: exp(x)*(exp(6*x) + 5)/6. - Elmo R. Oliveira, Aug 29 2024
MAPLE
a[0]:=0:a[1]:=1:for n from 2 to 50 do a[n]:=7*a[n-1]+1 od: seq(a[n]+1, n=0..19); # Zerinvary Lajos, Mar 20 2008
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
EXTENSIONS
a(20)-a(23) from Elmo R. Oliveira, Aug 29 2024
STATUS
approved