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A135420 a(n) = 4^n * 5^(n^2). 2
1, 20, 10000, 125000000, 39062500000000, 305175781250000000000, 59604644775390625000000000000, 291038304567337036132812500000000000000, 35527136788005009293556213378906250000000000000000 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

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

FORMULA

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

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 *)

CROSSREFS

Sequence in context: A250021 A203308 A109122 * A045811 A086687 A173790

Adjacent sequences:  A135417 A135418 A135419 * A135421 A135422 A135423

KEYWORD

nonn

AUTHOR

Philippe Deléham, Dec 11 2007

STATUS

approved

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Last modified December 5 12:24 EST 2021. Contains 349557 sequences. (Running on oeis4.)