A288836 a(n) = (1/3!)*3^(n+1)*(n+5)*(n+1)*(n).

18, 189, 1296, 7290, 36450, 168399, 734832, 3070548, 12400290, 48715425, 187067232, 704690766, 2611501074, 9542023155, 34437376800, 122941435176, 434685788658, 1523724783237, 5299912289520, 18305618105250, 62824881337218, 214364018189079, 727538485975056

Offset: 1

Author

Gregory Gerard Wojnar, Jun 17 2017

Keywords

• nonn

Links

• Harvey P. Dale, Table of n, a(n) for n = 1..1000
• Index entries for linear recurrences with constant coefficients, signature (12, -54, 108, -81).

Crossrefs

Column k=6 of A287768.

Cf. A288834, A288835, A288838.

Programs

Mathematica

LinearRecurrence[{12,-54,108,-81},{18,189,1296,7290},30] (* Harvey P. Dale, May 09 2025 *)

Formula

O.g.f.: z*3^2*(2-3*z)/(1-3*z)^4.

a(n) = -A287768(n+5,6).