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A331510 Array read by antidiagonals: A(n,k) is the number of nonequivalent binary matrices with k columns and any number of distinct nonzero rows with n ones in every column up to permutation of rows and columns. 7
1, 1, 1, 1, 1, 1, 1, 2, 0, 1, 1, 3, 1, 0, 1, 1, 5, 4, 0, 0, 1, 1, 7, 12, 3, 0, 0, 1, 1, 11, 36, 23, 1, 0, 0, 1, 1, 15, 124, 191, 30, 0, 0, 0, 1, 1, 22, 412, 2203, 837, 23, 0, 0, 0, 1, 1, 30, 1500, 31313, 41664, 2688, 12, 0, 0, 0, 1 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

0,8

LINKS

Table of n, a(n) for n=0..65.

FORMULA

A(n,k) = 0 for k > 0, n > 2^(k-1).

A(n,k) = A(2^(k-1) - n, k) for k > 0, n <= 2^(k-1).

EXAMPLE

Array begins:

=================================

n\k | 0 1 2 3  4   5    6   7

----+----------------------------

  0 | 1 1 1 1  1   1    1   1 ...

  1 | 1 1 2 3  5   7   11  15 ...

  2 | 1 0 1 4 12  36  124 412 ...

  3 | 1 0 0 3 23 191 2203 ...

  4 | 1 0 0 1 30 837 ...

  5 | 1 0 0 0 23 ...

  ...

The A(2,3) = 4 matrices are:

  [1 1 1]  [1 1 0]  [1 1 1]  [1 1 0]

  [1 0 0]  [1 0 1]  [1 1 0]  [1 0 1]

  [0 1 0]  [0 1 0]  [0 0 1]  [0 1 1]

  [0 0 1]  [0 0 1]

CROSSREFS

Rows n=1..3 are A000041, A331717, A331718.

Column k=5 is A331719.

Cf. A188445, A330942, A331461, A331508, A331509.

Sequence in context: A339218 A263412 A321258 * A319854 A124035 A204184

Adjacent sequences:  A331507 A331508 A331509 * A331511 A331512 A331513

KEYWORD

nonn,tabl,more

AUTHOR

Andrew Howroyd, Jan 18 2020

EXTENSIONS

a(58)-a(65) from Andrew Howroyd, Feb 08 2020

STATUS

approved

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Last modified July 28 00:54 EDT 2021. Contains 346316 sequences. (Running on oeis4.)