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A193623
Number of nonisomorphic Knuthian systems of order n^2.
0
1, 1, 3, 44, 14022, 207392556, 193491859167624, 16390160979986065741152
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OFFSET
1,3
COMMENTS
See the pdf file of the Curtis et al. reference for precise definition.
LINKS
Table of n, a(n) for n=1..8.
Frank Curtis, John Drew, Chi-Kwong Li and Daniel Pragel,
Central groupoids, central digraphs, and zero-one matrices A satisfying A^2 = J,
Journal of Combinatorial Theory, Series A, Volume 105 Issue 1, (2004) pp. 35-50.
F. Curtis, J. Drew,
Central groupoids, central digraphs, and zero-one matrices A satisfying A^2=J
, (2002), expanded version.
CROSSREFS
Sequence in context:
A337249
A259785
A369944
*
A102811
A307007
A142600
Adjacent sequences:
A193620
A193621
A193622
*
A193624
A193625
A193626
KEYWORD
nonn
AUTHOR
N. J. A. Sloane
, Jul 31 2011
STATUS
approved
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Last modified July 20 05:10 EDT 2024. Contains 374441 sequences. (Running on oeis4.)