A238383 Row sums of triangle in A139040.

1, 2, 3, 4, 6, 8, 11, 14, 18, 22, 28, 34, 43, 52, 65, 78, 97, 116, 144, 172, 213, 254, 314, 374, 462, 550, 679, 808, 997, 1186, 1463, 1740, 2146, 2552, 3147, 3742, 4614, 5486, 6764, 8042, 9915, 11788, 14533, 17278, 21301, 25324, 31220, 37116, 45757

Offset: 0

Author

Philippe Deléham, Feb 25 2014

Keywords

• easy
• nonn

Links

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

Crossrefs

Cf. A139040

Programs

Mathematica

LinearRecurrence[{1,1,-1,0,0,1,-1},{1,2,3,4,6,8,11},60] (* Harvey P. Dale, Jun 12 2017 *)

Formula

G.f.: (1+x^4)*(1+x)/((1-x)*(1-x^2-x^6)).

a(n) = a(n-1) + a(n-2) - a(n-3) + a(n-6) - a(n-7), a(0) = 1, a(1) = 2, a(2) = 3, a(3) = 4, a(4) = 6, a(5) = 8, a(6) = 11.