a(n) = ((9 + sqrt(5))^n - (9 - sqrt(5))^n)/(2*sqrt(5)).
A153886
a(n) = ((9 + sqrt(5))^n - (9 - sqrt(5))^n)/(2*sqrt(5)).
Terms
- a(0) =1a(1) =18a(2) =248a(3) =3096a(4) =36880a(5) =428544a(6) =4910912a(7) =55827072a(8) =631657984a(9) =7126986240a(10) =80279745536a(11) =903384465408
External references
- oeis: A153886