OFFSET
1,2
COMMENTS
Note that although the two Yordzhev papers have similar titles, they are different papers.
LINKS
Krasimir Yordzhev, On the Number of Disjoint Pairs of S-permutation Matrices, arXiv:12112:1628 [math.CO], 2012.
Krasimir Yordzhev, On the number of mutually disjoint pairs of S-permutation matrices, Discrete Mathematics 340 (2017) 1442-1448.
FORMULA
a(n) = A285178(n)*(n!)^(2*n)/2.
CROSSREFS
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, Apr 14 2017
STATUS
approved