OFFSET
1,2
COMMENTS
The condition that the rows be in nonincreasing order is equivalent to considering nonequivalent matrices up to permutation of rows.
FORMULA
a(n) = Sum{d|n} A331126(n/d, d).
a(p) = 2 for prime p.
EXAMPLE
The a(4) = 4 matrices are:
[1 0 0 0] [1] [1 0] [1 1]
[0 1 0 0] [1] [1 0] [1 0]
[0 0 1 0] [1] [0 1] [0 1]
[0 0 0 1] [1] [0 1]
CROSSREFS
KEYWORD
nonn
AUTHOR
Andrew Howroyd, Jan 15 2020
STATUS
approved