A076684 Odd terms in A027941.
1, 33, 609, 10945, 196417, 3524577, 63245985, 1134903169, 20365011073, 365435296161, 6557470319841, 117669030460993, 2111485077978049, 37889062373143905, 679891637638612257, 12200160415121876737
Offset: 0
Links
- Index entries for linear recurrences with constant coefficients, signature (19,-19,1).
Programs
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Mathematica
a[n_] := Fibonacci[6n+3]-1
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PARI
a(n)=fibonacci(6*n+3)-1
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PARI
a(n)=if(n<0,0,subst(poltchebi(n)+poltchebi(n+1),x,9)/5-1)
Formula
a(n) = F(6n+3) - 1 where F(k) denotes the k-th Fibonacci number.
G.f.: (1+14x+x^2)/((1-x)(1-18x+x^2)).