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Search: id:A052390
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| A052390 |
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Number of 4-element intersecting families (with not necessary distinct sets) whose union is an n-element set. |
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+0
1
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| 1, 7, 71, 956, 15116, 254397, 4318511, 72331966, 1188180386, 19152566087, 303768582701, 4755204310776, 73675434833456, 1132450098258577, 17301032324486891, 263098797953058386, 3987051131522775326
(list; graph; listen)
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OFFSET
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1,2
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REFERENCES
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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).
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FORMULA
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1/4!*(15^n-6*11^n+12*9^n-8^n-10*7^n+15*6^n-24*5^n+19*4^n+5*3^n-11*2^n+6)
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CROSSREFS
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Cf. A051181, A053156, A053157.
Sequence in context: A065537 A048552 A067307 this_sequence A002119 A146752 A022518
Adjacent sequences: A052387 A052388 A052389 this_sequence A052391 A052392 A052393
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KEYWORD
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nonn
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AUTHOR
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Vladeta Jovovic, Goran Kilibarda (vladeta(AT)eunet.rs), Mar 11 2000
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