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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
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 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,5

REFERENCES

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

LINKS

Table of n, a(n) for n=1..60.

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

EXAMPLE

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,

...

CROSSREFS

Sequence in context: A111848 A204384 A102412 * A185057 A343720 A048152

Adjacent sequences:  A260040 A260041 A260042 * A260044 A260045 A260046

KEYWORD

nonn,tabf

AUTHOR

N. J. A. Sloane, Jul 22 2015

STATUS

approved

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Last modified May 13 11:50 EDT 2021. Contains 343839 sequences. (Running on oeis4.)