A possible candidate for OEIS

[Dan Dima]

Hi all,

I search through OEIS but I did not find any sequence corresponding to the
following:

"A binary matrix is a matrix whose entries are all either 0 or 1. How many
n×n binary matrices A are there such that A*^2* is also a binary matrix? "

a(n) - n×n binary matrices A such that A*^2* is a binary matrix

a(1) = 2
a(2) = 11
a(3) = 172
  a(4) = 6327
a(5) = 474286
a(6) = 67147431
.....

Best regards,
Dan Dima
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