A188538 Row sums of triangle A156070.

1, 2, 2, 4, 6, 12, 23, 46, 90, 174, 330, 616, 1133, 2058, 3698, 6584, 11630, 20404, 35587, 61750, 106666, 183522, 314642, 537744, 916441, 1557842, 2642018, 4471276, 7552470, 12734364, 21436655, 36031486, 60478458, 101380758, 169740378, 283873144, 474246725

Offset

0,2

Links

Nathaniel Johnston, Table of n, a(n) for n = 0..301

Index entries for linear recurrences with constant coefficients, signature (4,-4,-2,4,0,-1).

Formula

G.f.: -(2*x^4-6*x^3+2*x^2+2*x-1) / ((x-1)^2*(x^2+x-1)^2). - Colin Barker, Jul 11 2015

a(n) = n+3 +A264147(n+1) -A000032(n+1). - R. J. Mathar, Jun 02 2022

Maple

with(combinat):A188538:=proc(n) local m, s; s:=1:for m from 1 to n do s:=s+1+fibonacci(n)-fibonacci(m)-fibonacci(n-m):od; return s; end: # Nathaniel Johnston, Apr 03 2011

Prog

(PARI) Vec(-(2*x^4-6*x^3+2*x^2+2*x-1)/((x-1)^2*(x^2+x-1)^2) + O(x^50)) \\ Colin Barker, Jul 11 2015

Crossrefs

Sequence in context: A052953 A128209 A274935 * A282164 A268175 A363578

Adjacent sequences: A188535 A188536 A188537 * A188539 A188540 A188541

Keyword

nonn,easy

Author

N. J. A. Sloane, Apr 03 2011

Extensions

Terms after a(10) from Nathaniel Johnston, Apr 03 2011

Status

approved