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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 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-x^2)*(1-4*x-4*x^2)). [Colin Barker, May 01 2012] 3*a(n) = A007985+2*A057087(n). - R. J. Mathar, Sep 29 2020 CROSSREFS Sequence in context: A126019 A071237 A006470 * A337905 A296661 A000181 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 August 7 16:00 EDT 2022. Contains 355994 sequences. (Running on oeis4.)