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A108081 Sum [i=0..n, C(2n-i,n+i) ]. 3
1, 2, 7, 25, 92, 344, 1300, 4950, 18955, 72905, 281403, 1089343, 4227273, 16438345, 64037453, 249855417, 976205516, 3818779616, 14954876080, 58623077586, 230007291334, 903164858092, 3549071519462, 13955918890440 (list; graph; refs; listen; history; internal format)
OFFSET

0,2

COMMENTS

A transform of the Fibonacci numbers A000045(n+1) under the mapping g(x)->(1/(c(x)sqrt(1-4x))g(xc(x)), c(x) the g.f. of A000108. Hankel transform is the bisection of the Fibonacci numbers F(2n+2) (A001906(n+1)). - Paul Barry (pbarry(AT)wit.ie), Sep 28 2007

Diagonal sums of A159965. [From Paul Barry (pbarry(AT)wit.ie), Apr 28 2009]

FORMULA

G.f.: 1/2*(1-5*x+4*x^2+((1-4*x)*(1-5*x)^2)^(1/2))/(1-4*x)/(1-4*x-x^2). - Vladeta Jovovic (vladeta(AT)eunet.rs), Sep 06 2006

G.f.: (1+sqrt(1-4x))/(2*sqrt(1-4x)*(x+sqrt(1-4x))); - Paul Barry (pbarry(AT)wit.ie), Sep 28 2007

a(n)=sum{k=0..n, C(n+k-1,k)F(n-k+1)}; - Paul Barry (pbarry(AT)wit.ie), Sep 28 2007

CROSSREFS

Sequence in context: A097613 A024482 A074605 * A199247 A116396 A150453

Adjacent sequences:  A108078 A108079 A108080 * A108082 A108083 A108084

KEYWORD

nonn

AUTHOR

Ralf Stephan, Jun 03 2005

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Last modified February 14 17:57 EST 2012. Contains 205655 sequences.