a(n) = Lucas(4*n+2) - 3 = 5*Fibonacci(2*n)*Fibonacci(2*n+2).

A081079

a(n) = Lucas(4*n+2) - 3 = 5*Fibonacci(2*n)*Fibonacci(2*n+2).

Terms

    a(0) =0a(1) =15a(2) =120a(3) =840a(4) =5775a(5) =39600a(6) =271440a(7) =1860495a(8) =12752040a(9) =87403800a(10) =599074575a(11) =4106118240a(12) =28143753120a(13) =192900153615

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