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A172720 Number of 9*n X 2*n 0..2 arrays with row sums 2 and column sums 9 1
3139, 3423871305383100, 34335031273255183438800013252500, 141178303808277520681079289672968415090175698600000, 52186319789297652611103763179819584756687013016766057690192910549000000 (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: A172929 A172945 A172961 * A276686 A252215 A250760

Adjacent sequences:  A172717 A172718 A172719 * A172721 A172722 A172723

KEYWORD

nonn

AUTHOR

R. H. Hardin Feb 06 2010

STATUS

approved

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Last modified November 29 18:41 EST 2021. Contains 349416 sequences. (Running on oeis4.)