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A286418 Array read by antidiagonals: T(n,m) = number of cycles in K_n X K_m 3
0, 0, 0, 1, 1, 1, 7, 14, 14, 7, 37, 170, 312, 170, 37, 197, 2904, 13945, 13945, 2904, 197, 1172, 74779, 1241696, 3228524, 1241696, 74779, 1172, 8018, 2751790, 196846257, 1723178763, 1723178763, 196846257, 2751790, 8018 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,7

COMMENTS

Equivalently, the number of undirected cycles in the n X m rook graph.

LINKS

Andrew Howroyd, Table of n, a(n) for n = 1..78

Eric Weisstein's World of Mathematics, Graph Cycle, Rook Graph

EXAMPLE

Table starts:

m\n  1    2       3          4             5

------------------------------------------------

1 |  0    0       1          7            37 ...

2 |  0    1      14        170          2904 ...

3 |  1   14     312      13945       1241696 ...

4 |  7  170   13945    3228524    1723178763 ...

5 | 37 2904 1241696 1723178763 6198979538330 ...

CROSSREFS

Main diagonal is A234624.

Row 1 is A002807.

Cf. A269562, A269565.

Sequence in context: A225556 A064666 A269160 * A040042 A233366 A232831

Adjacent sequences:  A286415 A286416 A286417 * A286419 A286420 A286421

KEYWORD

nonn,tabl

AUTHOR

Andrew Howroyd, May 08 2017

STATUS

approved

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Last modified December 8 02:04 EST 2019. Contains 329850 sequences. (Running on oeis4.)