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A051181 Number of 4-element intersecting families of an n-element set. 5
0, 0, 0, 4, 365, 11770, 278455, 5715094, 108498285, 1963243930, 34404675635, 589459538734, 9933916068505, 165358097339890, 2726894329246815, 44648990949187174 (list; graph; refs; listen; history; internal format)
OFFSET

0,4

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).

FORMULA

1/4!(16^n-6*12^n+12*10^n-9^n-22*8^n+15*7^n+12*6^n-17*5^n+17*4^n-11*3^n-6*2^n+6)

CROSSREFS

Cf. A036239, A051180-A051185.

Sequence in context: A051955 A177114 A109760 * A154682 A154569 A038015

Adjacent sequences:  A051178 A051179 A051180 * A051182 A051183 A051184

KEYWORD

nonn

AUTHOR

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

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Last modified February 14 05:41 EST 2012. Contains 205570 sequences.