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A331461
Array read by antidiagonals: A(n,k) is the number of nonequivalent binary matrices with k columns and any number of nonzero rows with n ones in every column up to permutation of rows and columns.
13
1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 3, 3, 1, 1, 1, 5, 8, 4, 1, 1, 1, 7, 23, 16, 5, 1, 1, 1, 11, 66, 93, 30, 6, 1, 1, 1, 15, 212, 652, 332, 50, 7, 1, 1, 1, 22, 686, 6369, 6414, 1062, 80, 8, 1, 1, 1, 30, 2389, 79568, 226041, 56712, 3117, 120, 9, 1, 1, 1, 42, 8682, 1256425, 12848128, 7295812, 441881, 8399, 175, 10, 1, 1
OFFSET
0,8
COMMENTS
A(n,k) is the number of non-isomorphic set multipartitions (multiset of sets) with k parts each part has size n.
LINKS
FORMULA
A306018(n) = Sum_{d|n} A(n/d, d).
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 1 3 8 23 66 212 686 ...
3 | 1 1 4 16 93 652 6369 79568 ...
4 | 1 1 5 30 332 6414 226041 12848128 ...
5 | 1 1 6 50 1062 56712 7295812 1817321457 ...
6 | 1 1 7 80 3117 441881 195486906 200065951078 ...
7 | 1 1 8 120 8399 3006771 4298181107 17131523059493 ...
...
The A(2,3) = 8 matrices are:
[1 0 0] [1 1 0] [1 1 1] [1 1 0] [1 1 0] [1 1 1] [1 1 0] [1 1 1]
[1 0 0] [1 0 0] [1 0 0] [1 1 0] [1 0 1] [1 1 0] [1 0 1] [1 1 1]
[0 1 0] [0 1 0] [0 1 0] [0 0 1] [0 1 0] [0 0 1] [0 1 1]
[0 1 0] [0 0 1] [0 0 1] [0 0 1] [0 0 1]
[0 0 1] [0 0 1]
[0 0 1]
PROG
(PARI) \\ See A304942 for Blocks
T(n, k)={Blocks(k, n*k, n)}
{ for(n=0, 7, for(k=0, 6, print1(T(n, k), ", ")); print) }
CROSSREFS
KEYWORD
nonn,tabl
AUTHOR
Andrew Howroyd, Jan 18 2020
STATUS
approved