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A199562
4*9^n+1.
1
5, 37, 325, 2917, 26245, 236197, 2125765, 19131877, 172186885, 1549681957, 13947137605, 125524238437, 1129718145925, 10167463313317, 91507169819845, 823564528378597, 7412080755407365, 66708726798666277, 600378541187996485
OFFSET
0,1
FORMULA
a(n) = 9*a(n-1)-8.
a(n) = 10*a(n-1)-9*a(n-2).
G.f.: (5-13*x)/((1-x)*(1-9*x)).
PROG
(Magma) [4*9^n+1: n in [0..30]];
CROSSREFS
Sequence in context: A176818 A359643 A068785 * A246540 A365842 A177395
KEYWORD
nonn,easy
AUTHOR
Vincenzo Librandi, Nov 08 2011
STATUS
approved