A097993 - OEIS

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A097993

Related to A097871.

1, 5, 120, 8831, 1248696, 275064055

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OFFSET

1,2

COMMENTS

In A097871, for each k, decide where the first k in row k will be and where the first k in column k will be. Suppose this partial matrix is K. Sequence gives the number of such K's.

LINKS

Table of n, a(n) for n=1..6.

CROSSREFS

Cf. A097871.

Sequence in context: A308363 A192639 A099123 * A172806 A054752 A258978

Adjacent sequences: A097990 A097991 A097992 * A097994 A097995 A097996

KEYWORD

nonn

AUTHOR

Guenter Stertenbrink (Sterten(AT)aol.com), Sep 08 2004

STATUS

approved