A336602 a(n) = 8*a(n-1) - 21*a(n-2) + 20*a(n-3) - 5*a(n-4), with initial terms a(0)=1, a(1)=7, a(2)=35, a(3)=154.

1, 7, 35, 154, 632, 2487, 9529, 35875, 133471, 492538, 1807268, 6604891, 24069905, 87539199, 317907067, 1153307002, 4180842064, 15147734815, 54860799881, 198634274203, 719047882103, 2602540622106, 9418700937340, 34084040705539, 123335178991777, 446277892754167, 1614771692630099

Offset: 0

Author

Peter Morris, Dec 20 2020

Keywords

• nonn
• easy

Links

• Index entries for linear recurrences with constant coefficients, signature (8,-21,20,-5).

Crossrefs

Extension of patterns illustrated in A001519, A033191, A033190, A094667, A030191, A094788.

Formula

G.f.: ( 1-x+x^3 ) / ( (5*x^2-5*x+1)*(x^2-3*x+1) ). - R. J. Mathar, May 05 2023

Extensions

Offset corrected by Jon E. Schoenfield, Feb 05 2021