OFFSET
1,2
FORMULA
a(n) = Sum_{d|n} A331568(d/n, d).
EXAMPLE
The a(2) = 4 matrices are:
[1 0] [0 1] [1 1] [2]
[0 1] [1 0]
CROSSREFS
KEYWORD
nonn
AUTHOR
Andrew Howroyd, Jan 24 2020
STATUS
approved