A198853 a(n) = 5*8^n - 1.

4, 39, 319, 2559, 20479, 163839, 1310719, 10485759, 83886079, 671088639, 5368709119, 42949672959, 343597383679, 2748779069439, 21990232555519, 175921860444159, 1407374883553279, 11258999068426239, 90071992547409919

Offset

0,1

Links

Vincenzo Librandi, Table of n, a(n) for n = 0..1000

Index entries for linear recurrences with constant coefficients, signature (9,-8).

Formula

a(n) = 8*a(n-1) + 7.

a(n) = 9*a(n-1) - 8*a(n-2), n > 1.

G.f.: ( 4+3*x ) / ( (8*x-1)*(x-1) ). - R. J. Mathar, Oct 31 2011

Prog

(Magma) [5*8^n-1: n in [0..30]]

Crossrefs

Sequence in context: A290559 A360740 A059945 * A093851 A224755 A241075

Adjacent sequences: A198850 A198851 A198852 * A198854 A198855 A198856

Keyword

nonn,easy

Author

Vincenzo Librandi, Oct 31 2011

Status

approved