A207836 a(n) = n*A052530(n)/2.

0, 3, 16, 75, 336, 1463, 6240, 26199, 108640, 445995, 1815792, 7341347, 29505840, 117982815, 469672384, 1862393775, 7359403968, 28991540051, 113892526800, 446305331451, 1744950085648, 6808253393415, 26513475730464, 103072540115975, 400058834841120

Offset: 2

Author

N. J. A. Sloane, Feb 21 2012

Keywords

• nonn
• easy

Links

• Colin Barker, Table of n, a(n) for n = 2..1000
• F. Goebel, A. A. Jagers, On a conjecture of Tutte concerning minimal tree numbers, J. Combin. Theory Ser. B 26 (1979), no. 3, 346-348. MR0535948 (80m:05064).
• Index entries for linear recurrences with constant coefficients, signature (8,-18,8,-1).

Crossrefs

Cf. A052530.

Programs

PARI

concat(0, Vec(x^3*(x^2-8*x+3)/(x^2-4*x+1)^2 + O(x^100))) \\ Colin Barker, Jun 08 2015

Formula

a(n) = 8*a(n-1)-18*a(n-2)+8*a(n-3)-a(n-4) for n>5. - Colin Barker, Jun 08 2015

G.f.: x^3*(x^2-8*x+3) / (x^2-4*x+1)^2. - Colin Barker, Jun 08 2015