a(n) = (8*sqrt(5)/25)((sqrt(5) + 2)((15 + 5*sqrt(5))/2)^n + (sqrt(5) - 2)((15 - 5*sqrt(5))/2)^n).

A109105

a(n) = (8*sqrt(5)/25)((sqrt(5) + 2)((15 + 5*sqrt(5))/2)^n + (sqrt(5) - 2)((15 - 5*sqrt(5))/2)^n).

Terms

    a(0) =40a(1) =520a(2) =6800a(3) =89000a(4) =1165000a(5) =15250000a(6) =199625000a(7) =2613125000a(8) =34206250000a(9) =447765625000

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