OFFSET
0,2
LINKS
Robert Israel, Table of n, a(n) for n = 0..1981
Index entries for linear recurrences with constant coefficients, signature (1, 7).
FORMULA
G.f.: (1+x)/(1-x-7*x^2) .
a(n) = Sum_{k=0..n+1} A122950(n+1,k)*6^(n+1-k). - Philippe Deléham, Jan 08 2008
a(n) = ((29 + 3*sqrt(29))/58)*(0.5 + 0.5*sqrt(29))^n + ((29 - 3*sqrt(29))/58)*(0.5 - 0.5*sqrt(29))^n. - Richard Choulet, Nov 20 2008
MAPLE
f:= gfun:-rectoproc({a(n) = a(n-1) + 7*a(n-2), a(0)=1, a(1)=2}, a(n), remember):
map(f, [$0..50]); # Robert Israel, Jul 23 2017
MATHEMATICA
LinearRecurrence[{1, 7}, {1, 2}, 30] (* Harvey P. Dale, Dec 09 2013 *)
PROG
(PARI) x='x+O('x^99); Vec((1+x)/(1-x-7*x^2)) \\ Altug Alkan, Jul 23 2017
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Philippe Deléham, Jan 03 2008
STATUS
approved