A289415 a(n) = ((11-sqrt(11))^n + (11+sqrt(11))^n) / 2.

1, 11, 132, 1694, 22748, 314116, 4408272, 62429224, 888533008, 12680511536, 181232622912, 2592261435104, 37094163051968, 530922829281856, 7599944308484352, 108797263565651584, 1557545924511056128, 22298311347021560576, 319232797938258158592

Offset

0,2

Links

Colin Barker, Table of n, a(n) for n = 0..850

Index entries for linear recurrences with constant coefficients, signature (22,-110).

Formula

G.f.: (1 - 11*x) / (1 - 22*x + 110*x^2).

a(n) = 22*a(n-1) - 110*a(n-2) for n>1.

Maple

a:= n-> (<<0|1>, <-110|22>>^n. <<1, 11>>)[1, 1]:
seq(a(n), n=0..25);  # Alois P. Heinz, Jul 06 2017

Prog

(PARI) Vec((1 - 11*x) / (1 - 22*x + 110*x^2) + O(x^25))

Crossrefs

Cf. A083881, A090139, A143079, A145301, A145302, A145303, A289414.

Sequence in context: A242163 A105280 A196731 * A051431 A014994 A015609

Adjacent sequences: A289412 A289413 A289414 * A289416 A289417 A289418

Keyword

nonn,easy

Author

Colin Barker, Jul 06 2017

Status

approved