A085532 (2n)^(n+1).

0, 4, 64, 1296, 32768, 1000000, 35831808, 1475789056, 68719476736, 3570467226624, 204800000000000, 12855002631049216, 876488338465357824, 64509974703297150976, 5097655355238390956032, 430467210000000000000000, 38685626227668133590597632

Offset: 0

Author

N. J. A. Sloane, Jul 05 2003

Keywords

• nonn

Programs

Maple

a:=n->mul(2*sum(1, j=2..n+1), k=1..n+1): seq(a(n), n=0..17); # Zerinvary Lajos, Jan 01 2009

Mathematica

Table[(2n)^(n+1),{n,0,20}] (* Harvey P. Dale, May 03 2011 *)