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A172617 Number of 9*n X 9 0..1 arrays with row sums 2 and column sums 2*n 1
14398171200, 109829050417159537464000, 2343976695927269878444049332219968000, 77695253876546044332382434342006457448342441400000 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

R. H. Hardin, Table of n, a(n) for n=1..11

CROSSREFS

Sequence in context: A134298 A046060 A172595 * A216015 A246109 A038545

Adjacent sequences:  A172614 A172615 A172616 * A172618 A172619 A172620

KEYWORD

nonn

AUTHOR

R. H. Hardin Feb 06 2010

STATUS

approved

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Last modified December 9 06:35 EST 2021. Contains 349627 sequences. (Running on oeis4.)