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A190955
a(n) = 10*a(n-1) + 5*a(n-2), with a(0)=0, a(1)=1.
4
0, 1, 10, 105, 1100, 11525, 120750, 1265125, 13255000, 138875625, 1455031250, 15244690625, 159722062500, 1673444078125, 17533051093750, 183697731328125, 1924642568750000, 20164914344140625, 211272356285156250, 2213548134572265625, 23191843127148437500
OFFSET
0,3
FORMULA
G.f.: x/(1 - 10*x - 5*x^2). - R. J. Mathar, Nov 21 2011
a(n+1) = Sum_{k=0..n} A099089(n,k)*5^k. - Philippe Deléham, Nov 21 2011
MATHEMATICA
LinearRecurrence[{10, 5}, {0, 1}, 50]
PROG
(PARI) x='x+O('x^30); concat([0], Vec(x/(1-10*x-5*x^2))) \\ G. C. Greubel, Jan 25 2018
(Magma) I:=[0, 1]; [n le 2 select I[n] else 10*Self(n-1) + 5*Self(n-2): n in [1..30]]; // G. C. Greubel, Jan 25 2018
CROSSREFS
Sequence in context: A077369 A068618 A096484 * A004343 A163166 A068767
KEYWORD
nonn
AUTHOR
STATUS
approved