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

Author

Gary W. Adamson, Sep 13 2008

Keywords

• nonn
• easy

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.

Examples

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

Links

• Colin Barker, Table of n, a(n) for n = 0..1000
• Index entries for linear recurrences with constant coefficients, signature (1,0,2).

Crossrefs

Cf. A118434.

Cf. A144182, A000587.

Programs

PARI

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

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)

Extensions

More terms from Alois P. Heinz, May 23 2015