A259319 a(n) = 2*A002309(n).

2, 164, 1414, 6216, 19338, 48620, 105742, 206992, 374034, 634676, 1023638, 1583320, 2364570, 3427452, 4842014, 6689056, 9060898, 12062148, 15810470, 20437352, 26088874, 32926476, 41127726, 50887088, 62416690, 75947092, 91728054, 110029304, 131141306, 155376028

Offset: 1

Author

N. J. A. Sloane, Jun 24 2015

Keywords

• nonn
• easy

Links

• Colin Barker, Table of n, a(n) for n = 1..1000
• J. L. Bailey, Jr., A table to facilitate the fitting of certain logistic curves, Annals Math. Stat., 2 (1931), 355-359.
• J. L. Bailey, A table to facilitate the fitting of certain logistic curves, Annals Math. Stat., 2 (1931), 355-359. [Annotated scanned copy]
• Index entries for linear recurrences with constant coefficients, signature (6,-15,20,-15,6,-1).

Crossrefs

Cf. A002309.

Programs

PARI

Vec(2*x*(x^4+76*x^3+230*x^2+76*x+1)/(x-1)^6 + O(x^100)) \\ Colin Barker, Jun 29 2015

Formula

a(n) = (2*n*(7-40*n^2+48*n^4))/15. - Colin Barker, Jun 29 2015

G.f.: 2*x*(x^4+76*x^3+230*x^2+76*x+1) / (x-1)^6. - Colin Barker, Jun 29 2015