A061180 Fifth column (m=4) of triangle A060920 (bisection of Fibonacci triangle, even part).

1, 20, 190, 1295, 7285, 36122, 163730, 693835, 2790100, 10758050, 40075630, 145052300, 512347975, 1772132390, 6018885570, 20118711993, 66306068715, 215797999830, 694463680160, 2212291834405, 6982976069384

Offset: 0

Author

Wolfdieter Lang, Apr 20 2001

Keywords

• nonn
• easy

Comments

Numerator polynomial of g.f. is sum(A061176(5,m)*x^m, m=0..5).

Links

• Index entries for linear recurrences with constant coefficients, signature (15, -95, 330, -685, 873, -685, 330, -95, 15, -1).

Crossrefs

Cf. A061179.

Programs

Mathematica

CoefficientList[Series[((1-x^5)+5(x-x^4)-15(x^2-x^3))/(1-3x+x^2)^5,{x,0,40}],x] (* or *) LinearRecurrence[{15,-95,330,-685,873,-685,330,-95,15,-1},{1,20,190,1295,7285,36122,163730,693835,2790100,10758050},30] (* Harvey P. Dale, Sep 01 2022 *)

Formula

a(n) = A060920(n+4,4).

G.f.: ((1-x^5)+5*(x-x^4)-15*(x^2-x^3))/(1-3*x+x^2)^5.