a(n) = Fibonacci(4n+2) - 1, or Fibonacci(2n)*Lucas(2n+2).

A081008

a(n) = Fibonacci(4n+2) - 1, or Fibonacci(2n)*Lucas(2n+2).

Terms

    a(0) =0a(1) =7a(2) =54a(3) =376a(4) =2583a(5) =17710a(6) =121392a(7) =832039a(8) =5702886a(9) =39088168a(10) =267914295a(11) =1836311902a(12) =12586269024a(13) =86267571271a(14) =591286729878

External references