A229163 - OEIS

A229163

Number of n X n binary matrices with exactly 4 ones in each row and column, and with rows and columns in lexicographically nondecreasing order.

%I #19 Apr 15 2016 14:33:01

%S 0,0,0,1,1,5,161,7776,626649

%N Number of n X n binary matrices with exactly 4 ones in each row and column, and with rows and columns in lexicographically nondecreasing order.

%D K. Yordzhev, On an Algorithm for Isomorphism-Free Generations of Combinatorial Objects, International Journal of Emerging Trends & Technology in Computer Science (IJETTCS), Web Site: www.ijettcs.org, Volume 2, Issue 6, November - December 2013, ISSN 2278-6856

%H K. Yordzhev, <a href="http://arXiv.org/abs/1305.6790">Fibonacci sequence related to a combinatorial problem on binary matrices</a>, arXiv preprint arXiv:1305.6790, 2013

%H K. Yordzhev, <a href="http://arxiv.org/abs/1506.04642">Semi-canonical binary matrices</a>, arXiv preprint arXiv:1506.04642, 2015

%Y Cf. A229161-A229164, A000513.

%Y A column of A227061.

%K nonn,more

%O 1,6

%A _N. J. A. Sloane_, Sep 15 2013