a(n) = 4^n * T(n,3/2) where T is the Chebyshev polynomial of the first kind.

A099140

a(n) = 4^n * T(n,3/2) where T is the Chebyshev polynomial of the first kind.

Terms

    a(0) =1a(1) =6a(2) =56a(3) =576a(4) =6016a(5) =62976a(6) =659456a(7) =6905856a(8) =72318976a(9) =757334016a(10) =7930904576a(11) =83053510656a(12) =869747654656

External references