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A051363
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Number of 6-element families of an n-element set such that every 3 members of the family have a non-empty intersection.
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0
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0, 0, 0, 0, 112, 40286, 5485032, 534844548, 45066853496, 3538771308282, 267882021563464, 19861835713621616, 1453175611052688600, 105278656040052332838, 7564280930105061931496, 539399446172552069053404
(list; graph; refs; listen; history; internal format)
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OFFSET
| 0,5
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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).
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FORMULA
| 1/6! (64^n-20*56^n + 90*52^n + 30*50^n + 25*49^n-420*48^n-180*47^n + 450*46^n + 60*45^n + 615*44^n + 1683*43^n-3252*42^n-6030*41^n + 8520*40^n + 10560*39^n-15849*38^n-13005*37^n + 26410*36^n + 10655*35^n-50385*34^n + 33390*33^n + 29480*32^n-82010*31^n + 91215*30^n-67380*29^n + 36870*28^n-15249*27^n + 4380*26^n-1215*25^n + 1390*24^n-695*23^n-1574*22^n + 3255*21^n-3075*20^n + 1800*19^n-675*18^n + 150*17^n + 70*16^n-340*14^n + 510*13^n-340*12^n + 85*11^n-225*8^n + 225*7^n + 274*4^n-274*3^n-120*2^n + 120)
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CROSSREFS
| Cf. A036239, A051180-A051185.
Sequence in context: A206310 A063409 A051366 * A184898 A180039 A159432
Adjacent sequences: A051360 A051361 A051362 * A051364 A051365 A051366
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KEYWORD
| nonn
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AUTHOR
| Vladeta Jovovic, Goran Kilibarda (vladeta(AT)eunet.rs)
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