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A172721 Number of 9*n X 9 0..2 arrays with row sums 2 and column sums 2*n 1
41514583320, 2402820978940192425615000, 384184227197088213207839624049360408000, 95131219937961621952706904277268129938808819520975000 (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: A199428 A287261 A172631 * A259350 A237495 A227387

Adjacent sequences:  A172718 A172719 A172720 * A172722 A172723 A172724

KEYWORD

nonn

AUTHOR

R. H. Hardin Feb 06 2010

STATUS

approved

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Last modified December 2 05:01 EST 2021. Contains 349437 sequences. (Running on oeis4.)