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A226321
Number of real {0,1} matrices n X n which are the square of a {0,1} matrix.
2
1, 2, 8, 88, 3245, 254411, 37324414
OFFSET
0,2
COMMENTS
A121231(n) >= a(n).
EXAMPLE
The 8 solutions when n=2 are:
00 00 00 01 10 10 10 11
00 01 11 01 00 01 10 00
- from N. J. A. Sloane, Jun 03 2013
CROSSREFS
Sequence in context: A009144 A132316 A136749 * A054955 A012299 A012295
KEYWORD
nonn,more,hard
AUTHOR
Giovanni Resta, Jun 03 2013
STATUS
approved