A135420 a(n) = 4^n * 5^(n^2).

1, 20, 10000, 125000000, 39062500000000, 305175781250000000000, 59604644775390625000000000000, 291038304567337036132812500000000000000, 35527136788005009293556213378906250000000000000000

Offset: 0

Author

Philippe Deléham, Dec 11 2007

Keywords

• nonn

Comments

Hankel transform of A132864.

For n>0, a(n) is even with a last digit of 0 and is 1 when n=0. - Wesley Ivan Hurt, Dec 04 2013

Links

• G. C. Greubel, Table of n, a(n) for n = 0..25

Programs

Maple

A135420:=n->4^n*5^(n^2); seq(A135420(n), n=0..10); # Wesley Ivan Hurt, Dec 04 2013

Mathematica

Table[4^n*5^(n^2), {n,0,10}] (* Wesley Ivan Hurt, Dec 04 2013 *)

Formula

a(n) = 4^n*5^(n^2) = A000302(n) * A060758(n).