A144181 INVERT transform of A118434, = row sums of triangle A144182.

1, 1, 3, 9, 11, 17, 35, 57, 91, 161, 275, 457, 779, 1329, 2243, 3801, 6459, 10945, 18547, 31465, 53355, 90449, 153379, 260089, 440987, 747745, 1267923, 2149897, 3645387, 6181233, 10481027, 17771801, 30134267, 51096321, 86639923, 146908457, 249101099

Offset

0,3

Comments

A118434 = row sums of the self-inverse triangle A118433 (a generator for the Rao Uppuluri-Carpenter numbers, A000587).

A144181 = row sums of triangle A144182.

Links

Colin Barker, Table of n, a(n) for n = 0..1000

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

Formula

Equals row sums of triangle A144182 and INVERT transform of A118434: (1, 0, 2, 4, -4, 0, -8, -16, 16, 0, 32,...).

From Colin Barker, Aug 21 2016: (Start)

a(n) = a(n-1)+2*a(n-3) for n>3.

G.f.: (1+2*x^2+4*x^3) / (1-x-2*x^3).

(End)

Example

a(3) = 9 = sum of row 3 terms, triangle A144182: (4 + 2 + 0 + 3).

Prog

(PARI) Vec((1+2*x^2+4*x^3)/(1-x-2*x^3) + O(x^40)) \\ Colin Barker, Aug 21 2016

Crossrefs

Cf. A118434.

Cf. A144182, A000587.

Sequence in context: A227245 A173394 A111211 * A004626 A110999 A179867

Adjacent sequences: A144178 A144179 A144180 * A144182 A144183 A144184

Keyword

nonn,easy

Author

Gary W. Adamson, Sep 13 2008

Extensions

More terms from Alois P. Heinz, May 23 2015

Status

approved