A333740 - OEIS

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A333740

Number of inequivalent 2n X 2n binary matrices with rows and columns summing to n, where equivalence means permutations of rows or columns.

2

1, 1, 2, 7, 194, 601055, 294494683312, 14584161564179926207, 80055722734531008786502722278, 53505113579082591021525466231199449015539

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OFFSET

0,3

LINKS

Table of n, a(n) for n=0..9.

Index entries for sequences related to binary matrices

Index to number of inequivalent matrices modulo permutation of rows and columns

FORMULA

a(n) = A133687(2n,n).

CROSSREFS

Sequence in context: A307582 A125610 A247028 * A306951 A181864 A096463

Adjacent sequences: A333737 A333738 A333739 * A333741 A333742 A333743

KEYWORD

nonn,more

AUTHOR

Alois P. Heinz, Apr 03 2020

STATUS

approved