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A055194 Number of 3 X n binary matrices with distinct rows, up to row and column permutation; (n,3)-hypergraphs (including empty hyperedge but excluding multiple hyperedges). 1
3, 16, 52, 134, 302, 614, 1159, 2064, 3504, 5716, 9018, 13818, 20643, 30158, 43190, 60758, 84110, 114746, 154469, 205422, 270132, 351562, 453172, 578962, 733551, 922238, 1151072, 1426932, 1757618, 2151920, 2619731, 3172138, 3821524 (list; graph; refs; listen; history; text; internal format)
OFFSET

2,1

LINKS

Table of n, a(n) for n=2..34.

FORMULA

G.f. : -x^2*(x^8-2*x^6-2*x^5+4*x^3-4*x-3)/((x^3-1)^2*(x^2-1)^2*(x-1)^4).

CROSSREFS

Cf. A002727.

Sequence in context: A089363 A000574 A041233 * A190730 A173052 A027540

Adjacent sequences:  A055191 A055192 A055193 * A055195 A055196 A055197

KEYWORD

easy,nonn

AUTHOR

Vladeta Jovovic, Jun 30 2000

EXTENSIONS

More terms from James A. Sellers, Jul 04 2000

STATUS

approved

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Last modified March 30 22:55 EDT 2020. Contains 333132 sequences. (Running on oeis4.)