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A106514 Expansion of (1-x)/((1-2x)(1-2x-x^2)). 1
1, 3, 9, 25, 67, 175, 449, 1137, 2851, 7095, 17553, 43225, 106051, 259423, 633089, 1541985, 3749827, 9107175, 22095249, 53559817, 129739171, 314086735, 760009793, 1838300625, 4444999651, 10745077143, 25968708369, 62749602745 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

Convolution of A000079 and A001333. Row sums of A106513.

Equals eigensequence of a triangle with the Pell series as the left border and the rest 1's. - Gary W. Adamson, Jul 24 2010

LINKS

Table of n, a(n) for n=0..27.

FORMULA

a(n)=sum{k=0..n, 2^(n-k)((1-sqrt(2))^k+(1+sqrt(2))^k)/2}; a(n)=sum{k=0..n, sum{j=0..floor((n+1)/2), binomial(n+1, 2j+k+1)2^j}}.

a(n) = Pell(n+3) - Pell(n+2) - 2^(n+1) = A001333(n+2) - 2^(n+1). - Ralf Stephan, Jun 02 2007

CROSSREFS

Sequence in context: A081663 A245748 A181383 * A268451 A156561 A085327

Adjacent sequences:  A106511 A106512 A106513 * A106515 A106516 A106517

KEYWORD

easy,nonn

AUTHOR

Paul Barry, May 05 2005

STATUS

approved

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Last modified February 16 12:48 EST 2019. Contains 320163 sequences. (Running on oeis4.)