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

0,2

Links

Table of n, a(n) for n=0..48.

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

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.

Mathematica

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

Crossrefs

Cf. A139040

Sequence in context: A059291 A177339 A075535 * A134953 A175870 A114829

Adjacent sequences: A238380 A238381 A238382 * A238384 A238385 A238386

Keyword

easy,nonn

Author

Philippe Deléham, Feb 25 2014

Status

approved