A051184 Number of 7-element intersecting families of an n-element set.

0, 0, 0, 0, 80, 169125, 71102400, 18047221707, 3623784887164, 638772147728325, 103751227132038920, 15931275037246743999, 2348130220089143792148, 335520750110815538499945, 46803828588394634589433120

Offset

0,5

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).

Links

Table of n, a(n) for n=0..14.

Formula

1/7! (128^n - 21*96^n + 105*80^n - 35*72^n + 105*68^n - 42*66^n + 7*65^n - 476*64^n - 630*60^n + 1785*56^n + 315*54^n - 210*52^n - 105*51^n + 1260*50^n - 105*49^n - 1575*48^n - 2520*46^n - 105*45^n + 1638*44^n + 840*43^n - 6615*42^n + 1050*41^n + 4130*40^n - 1890*39^n + 14595*38^n + 2835*37^n - 7945*36^n - 1554*35^n - 18711*34^n - 12572*33^n + 24710*32^n + 4620*31^n + 560*30^n + 25995*29^n - 16905*28^n - 13545*27^n - 6510*26^n - 42945*25^n + 12005*24^n + 102011*23^n - 4648*22^n - 87780*21^n - 15785*20^n + 43120*19^n + 21364*18^n + 4200*17^n - 37205*16^n - 17105*15^n + 36386*14^n + 28644*13^n - 57603*12^n + 24150*11^n + 4585*10^n - 16289*9^n + 20943*8^n - 12754*7^n - 287*6^n + 4137*5^n - 3388*4^n + 1764*3^n + 720*2^n - 720)

Crossrefs

Cf. A036239, A051180-A051185.

Sequence in context: A159391 A323448 A231036 * A159444 A208187 A116230

Adjacent sequences: A051181 A051182 A051183 * A051185 A051186 A051187

Keyword

nonn

Author

Vladeta Jovovic, Goran Kilibarda

Status

approved