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A126946
The sequence b[n] defined in A126940.
2
0, 2, 4, 12, 40, 128, 404, 1282, 4076, 12946, 41110, 130570, 414708, 1317126, 4183250, 13286248, 42197850, 134022604, 425663006, 1351928684, 4293798244, 13637334278, 43312907878, 137564127106, 436911072754, 1387653086532, 4407260902428, 13997697874880
OFFSET
0,2
COMMENTS
Linear recurrence and empirical g.f confirmed for more terms. - Ray Chandler, Mar 07 2024
FORMULA
Empirical g.f.: 2*x*(x^3-x^2-1) / (x^6+4*x^5+4*x^4+7*x^3+x^2+2*x-1). - Colin Barker, Apr 08 2013
CROSSREFS
Sequence in context: A170808 A366579 A099214 * A113179 A214761 A327845
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, Mar 18 2007
STATUS
approved