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%I #13 Oct 08 2017 13:26:39
%S 0,0,0,0,225,21571,1174122,51441824,2038356243,76714338477,
%T 2804947403364,100732231517698,3572491367063421,125474030774355263,
%U 4371052010746528926,151172238539268318372
%N Number of 5-element families of an n-element set such that every 3 members of the family have a nonempty intersection.
%D 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).
%H G. C. Greubel, <a href="/A051364/b051364.txt">Table of n, a(n) for n = 0..660</a>
%F a(n) = (1/5!)*(32^n - 10*28^n + 30*26^n + 5*25^n - 80*24^n + 45*23^n + 105*22^n - 217*21^n + 205*20^n - 120*19^n + 45*18^n - 10*17^n - 9*16^n + 40*14^n - 60*13^n + 40*12^n - 10*11^n + 35*8^n - 35*7^n - 50*4^n + 50*3^n + 24*2^n - 24).
%t Table[1/5! (32^n - 10*28^n + 30*26^n + 5*25^n - 80*24^n + 45*23^n + 105*22^n - 217*21^n + 205*20^n - 120*19^n + 45*18^n - 10*17^n - 9*16^n + 40*14^n - 60*13^n + 40*12^n - 10*11^n + 35*8^n - 35*7^n - 50*4^n + 50*3^n + 24*2^n - 24), {n, 0, 50}] (* _G. C. Greubel_, Oct 08 2017 *)
%Y Cf. A036239, A051180, A051181, A051182, A051183, A051184, A051185.
%K nonn
%O 0,5
%A _Vladeta Jovovic_, Goran Kilibarda
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