%I A016103
%S A016103 1,15,151,1275,9751,70035,481951,3216795,20991751,134667555,
%T A016103 852639151,5343198315,33212784151,205111785075,1260114546751,
%U A016103 7708980203835,46999640806951,285743822630595,1733261544204751
%N A016103 Expansion of 1/((1-4x)(1-5x)(1-6x)).
%C A016103 2*a(n-2) = 6^n-2*5^n+4^n is the number of 3 X n {0,1}-matrices such that:
(a) first and second row have a common 1, (b) first and third row
have a common 1, (c) second and third row have no a common 1. - Andy
Fugard (a.fugard(AT)ed.ac.uk) and Vladeta Jovovic (vladeta(AT)eunet.rs),
Jul 26 2008
%H A016103 Andy Fugard, <a href="http://figuraleffect.googlepages.com/note1657r2.pdf">
Counting first-order models (with n individuals) of syllogisms</a>
.
%F A016103 a(n) = (4^n + 6^n - 2*5^n) /2. - Andy Fugard, Jul 22 2008
%F A016103 If we define f(m,j,x)=sum(binomial(m,k)*stirling2(k,j)*x^(m-k),k=j..m)
then a(n-2)=f(n,2,4), (n>=2). [From Milan R. Janjic (agnus(AT)blic.net),
Apr 26 2009]
%Y A016103 Cf. A051588.
%Y A016103 Sequence in context: A081135 A084902 A021364 this_sequence A041424 A021124
A004322
%Y A016103 Adjacent sequences: A016100 A016101 A016102 this_sequence A016104 A016105
A016106
%K A016103 nonn
%O A016103 0,2
%A A016103 Robert G. Wilson v (rgwv(AT)rgwv.com)
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