A027017 a(n) = T(2*n+1, n+2), T given by A027011.

1, 7, 73, 373, 1404, 4506, 13226, 36889, 99947, 266455, 704150, 1852212, 4860468, 12739243, 33369709, 87385081, 228803856, 599048334, 1568366942, 4106082685, 10749916175, 28143706267, 73681248938, 192900093288, 505019090664, 1322157246031, 3461452722961

Offset

1,2

Links

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

Index entries for linear recurrences with constant coefficients, signature (7,-19,26,-19,7,-1).

Formula

G.f.: x*(1+43*x^2-31*x^3+17*x^4-7*x^5+x^6) / ((1-x)^4*(1-3*x+x^2)). - Colin Barker, Feb 19 2016

Prog

(PARI) Vec(x*(1+43*x^2-31*x^3+17*x^4-7*x^5+x^6)/((1-x)^4*(1-3*x+x^2)) + O(x^40)) \\ Colin Barker, Feb 19 2016

Crossrefs

Sequence in context: A139966 A175205 A373685 * A076106 A202042 A294291

Adjacent sequences: A027014 A027015 A027016 * A027018 A027019 A027020

Keyword

nonn,easy

Author

Clark Kimberling

Status

approved