A323266 A323265(n)/2.

0, 1, 3, 13, 51, 208, 842, 3419, 13873, 56303, 228487, 927252, 3762976, 15270937, 61972603, 251497601, 1020629091, 4141923220, 16808778106, 68213486019, 276824385713, 1123410413427, 4559031003423, 18501487472296, 75082849498048, 304701678564513, 1236542213577475, 5018143166006245

Offset

1,3

Links

Colin Barker, Table of n, a(n) for n = 1..1000

Index entries for linear recurrences with constant coefficients, signature (5,-3,-5,7,-1).

Formula

From Colin Barker, Jan 16 2019: (Start)

G.f.: x^2*(1 - x)^2 / (1 - 5*x + 3*x^2 + 5*x^3 - 7*x^4 + x^5).

a(n) = 5*a(n-1) - 3*a(n-2) - 5*a(n-3) + 7*a(n-4) - a(n-5) for n>5.

(End)

Mathematica

LinearRecurrence[{5, -3, -5, 7, -1}, {0, 1, 3, 13, 51}, 30] (* Harvey P. Dale, May 20 2021 *)

Prog

(PARI) concat(0, Vec(x^2*(1 - x)^2 / (1 - 5*x + 3*x^2 + 5*x^3 - 7*x^4 + x^5) + O(x^30))) \\ Colin Barker, Jan 16 2019

Crossrefs

Cf. A323265.

Sequence in context: A015521 A360874 A270913 * A146279 A098619 A086608

Adjacent sequences: A323263 A323264 A323265 * A323267 A323268 A323269

Keyword

nonn,easy

Author

N. J. A. Sloane, Jan 09 2019

Status

approved