a(n) = 6*a(n-1) - 8*a(n-2) + 4 for n > 1; a(0) = 1, a(1) = 9.

A171480

a(n) = 6*a(n-1) - 8*a(n-2) + 4 for n > 1; a(0) = 1, a(1) = 9.

Terms

    a(0) =1a(1) =9a(2) =50a(3) =232a(4) =996a(5) =4124a(6) =16780a(7) =67692a(8) =271916a(9) =1089964a(10) =4364460a(11) =17467052a(12) =69886636a(13) =279583404a(14) =1118407340a(15) =4473776812a(16) =17895402156a(17) =71582198444a(18) =286329973420

External references