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A105867 A generalized Chebyshev transform of the Jacobsthal numbers. 0
0, 1, 1, 7, 11, 47, 95, 327, 759, 2343, 5863, 17095, 44551, 126023, 335687, 934343, 2518215, 6948807, 18846663, 51765703, 140875207, 385980871, 1052314055, 2879386055, 7857807815, 21485572551, 58664391111, 160344666567 (list; graph; refs; listen; history; internal format)
OFFSET

0,4

COMMENTS

Apply the Riordan array (1/(1-2x^2),x/(1-2x^2)) to A001045.

FORMULA

G.f.: x/(1-x-6x^2+2x^3+4x^4); a(n)=sum{k=0..floor(n/2), 2^k*C(n-k, k)*A001045(n-2k)}; a(n)=sqrt(3)(sqrt(3)+1)^(n+1)/18+sqrt(3)(sqrt(3)-1)^(n+1)(-1)^n/18-2^(n+1)(-1)^n/9-1/9.

CROSSREFS

Sequence in context: A062209 A086828 A117392 * A166653 A057290 A003599

Adjacent sequences:  A105864 A105865 A105866 * A105868 A105869 A105870

KEYWORD

easy,nonn

AUTHOR

Paul Barry (pbarry(AT)wit.ie), Apr 23 2005

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Last modified February 17 09:41 EST 2012. Contains 206009 sequences.