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A084169 A Pell Jacobsthal product. 0
0, 1, 2, 15, 60, 319, 1470, 7267, 34680, 168435, 810898, 3921103, 18918900, 91381991, 441150502, 2130258075, 10285325040, 49663079099, 239791814010, 1157823924167, 5590452446700, 26993130847215, 130334271942158 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

LINKS

Table of n, a(n) for n=0..22.

Index entries for linear recurrences with constant coefficients, signature (2,13,4,-4).

FORMULA

a(n) = ((sqrt(2)+1)^n*(2^n-(-1)^n)-(sqrt(2)-1)^n*((-2)^n-1))*sqrt(2)/12.

a(n) = A001045(n)*A000129(n).

G.f.: x*(1-2*x^2)/(1-2*x-13*x^2-4*x^3+4*x^4). [Colin Barker, May 01 2012]

CROSSREFS

Sequence in context: A126019 A071237 A006470 * A296661 A000181 A047146

Adjacent sequences:  A084166 A084167 A084168 * A084170 A084171 A084172

KEYWORD

nonn,easy

AUTHOR

Paul Barry, May 18 2003

STATUS

approved

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Last modified October 16 13:12 EDT 2018. Contains 316263 sequences. (Running on oeis4.)