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A051185 Number of intersecting families of an n-element set. Also number of n-variable clique Boolean functions. 14
2, 6, 40, 1376, 1314816, 912818962432, 291201248266450683035648 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

COMMENTS

These values are necessarily divisble by powers of 2. The powers begin 1, 1, 3, 5, 12, 22, 49, which are A121482(2) through A121482(8).

a(1) = 2^1.

a(2) = 6 = 2^1 * 3

a(3) = 2^3 * 5.

a(4) = 2^5 * 43.

a(5) = 2^12 * 3 * 107.

a(6) = 2^22 * 13 * 16741.

a(7) = 2^49 * 2111 * 245039.

REFERENCES

V. Jovovic, G. Kilibarda, On the number of Boolean functions in the Post classes F^{mu}_8, Diskretnaya Matematika, 11 (1999), no. 4, 127-138 (translated in Discrete Mathematics and Applications, 9, (1999), no. 6).

Pogosyan G., Miyakawa M., A. Nozaki, Rosenberg I., The Number of Clique Boolean Functions, IEICE Trans. Fundamentals, Vol. E80-A, No. 8, pp. 1502-1507, 1997/8.

LINKS

Index entries for sequences related to Boolean functions

Pogosyan et al., Number of Clique Boolean Functions

CROSSREFS

Cf. A036239, A051180-A051184.

Sequence in context: A045846 A199574 A135755 * A118623 A000612 A096138

Adjacent sequences:  A051182 A051183 A051184 * A051186 A051187 A051188

KEYWORD

hard,nonn,nice

AUTHOR

Vladeta Jovovic, Goran Kilibarda (vladeta(AT)eunet.rs)

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Last modified February 17 20:50 EST 2012. Contains 206085 sequences.