A260043 Irregular triangle read by rows: T(n,k) (n >= 1, 0 <= k <= n^2) = number of n X n (0,1) real matrices with k zeros and permanent zero.

0, 1, 0, 0, 4, 4, 1, 0, 0, 0, 6, 45, 90, 78, 36, 9, 1, 0, 0, 0, 0, 8, 96, 576, 2128, 4860, 676, 6496, 4080, 1796, 560, 120, 16, 1, 0, 0, 0, 0, 0, 10, 200, 1900, 11500, 50025, 166720, 439600, 923700, 1534800, 1994200, 2010920, 1571525, 956775, 458500, 174700, 53010, 12650, 2300, 300, 25, 1

Offset: 1

Author

N. J. A. Sloane, Jul 22 2015

Keywords

• nonn
• tabf

Examples

			Triangle begins:
0,1,
0,0,4,4,1,
0,0,0,6,45,90,78,36,9,1,
0,0,0,0,8,96,576,2128,4860,676,6496,4080,1796,560,120,16,1,
0,0,0,0,0,10,200,1900,11500,50025,166720,439600,923700,1534800,1994200,2010920,1571525,956775,458500,174700,53010,12650,2300,300,25,1,
...
		

References

• M. B. Wells, Elements of Combinatorial Computing. Pergamon, Oxford, 1971, see p. 240.

Links

• M. B. Wells, Elements of Combinatorial Computing, Pergamon, Oxford, 1971. [Annotated scanned copy of pages 237-240]