a(n) = ((1 + sqrt(4*n^2 + 1))^n + (1 - sqrt(4*n^2 + 1))^n)/2^n.
A320534
a(n) = ((1 + sqrt(4*n^2 + 1))^n + (1 - sqrt(4*n^2 + 1))^n)/2^n.
Terms
- a(0) =2a(1) =1a(2) =9a(3) =28a(4) =577a(5) =3251a(6) =105193a(7) =857501a(8) =37831169a(9) =403541596a(10) =22550351001a(11) =297238464799
External references
- oeis: A320534