A133953 Expansion of 2*x*(1+x)*(1-2*x)/((1-x)^2*(1-2*x-x^2)).

2, 6, 12, 24, 50, 110, 252, 592, 1410, 3382, 8140, 19624, 47346, 114270, 275836, 665888, 1607554, 3880934, 9369356, 22619576, 54608434, 131836366, 318281084, 768398448, 1855077890, 4478554134, 10812186060, 26102926152, 63018038258

Offset

1,1

Links

Table of n, a(n) for n=1..29.

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

Formula

G.f.: 2*x*(1+x)*(1-2*x)/((1-x)^2*(1-2*x-x^2)). [Colin Barker, Feb 28 2012]

Crossrefs

Sequence in context: A309841 A132176 A197469 * A350293 A122863 A170935

Adjacent sequences: A133950 A133951 A133952 * A133954 A133955 A133956

Keyword

nonn,easy,less

Author

Roger L. Bagula, Jan 08 2008

Extensions

Meaningful name from Joerg Arndt, Dec 26 2022

Status

approved