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A088309 Number of equivalence classes of n X n (0,1)-matrices with all rows distinct and all columns distinct. 15
1, 2, 5, 44, 1411, 159656, 62055868, 82060884560, 371036717493194, 5812014504668066528, 320454239459072905856944, 63156145369562679089674952768, 45090502574837184532027563736271152, 117910805393665959622047902193019284914432, 1139353529410754170844431642119963019965901238144 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

Two such matrices are equivalent if they differ just by a permutation of the rows.

REFERENCES

G. Kilibarda and Vladeta Jovovic, "Enumeration of some classes of T_0-hypergraphs", in preparation, 2004.

LINKS

Table of n, a(n) for n=0..14.

FORMULA

Sum_{k=0..n} Stirling1(n, k)*binomial(2^k, n). - Vladeta Jovovic, Nov 07 2003

a(n) = A088310(n) / n!.

EXAMPLE

a(2) = 5: 00/01, 00/10, 01/10, 01/11, 10/11.

CROSSREFS

Cf. A088229, A088310, A088616.

Main diagonal of A059084.

Binary matrices with distinct rows and columns, various versions: A059202, A088309, A088310, A088616, A089673, A089674, A093466, A094000, A094223, A116532, A116539, A181230, A259763

Sequence in context: A225724 A163115 A221682 * A056680 A005166 A121621

Adjacent sequences:  A088306 A088307 A088308 * A088310 A088311 A088312

KEYWORD

nonn

AUTHOR

N. J. A. Sloane, Nov 07 2003

EXTENSIONS

Suggested by Yuval Dekel (dekelyuval(AT)hotmail.com), Nov 06 2003

a(0)-a(5) from W. Edwin Clark, Nov 07 2003

STATUS

approved

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Last modified January 18 13:09 EST 2019. Contains 319271 sequences. (Running on oeis4.)