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A244165 Number of compositions of n in which the minimal multiplicity of parts equals 2.

%I A244165 #4 Jun 21 2014 15:59:24
%S A244165 1,0,1,0,7,10,32,31,71,77,222,342,971,1936,4681,9662,19440,38304,
%T A244165 76458,143542,281447,536472,1051100,2039870,4055916,8030958,16168611,
%U A244165 32510383,65705473,132895297,269206168,544002516,1099360989,2217243856,4464684513,8975720721
%N A244165 Number of compositions of n in which the minimal multiplicity of parts equals 2.
%H A244165 Alois P. Heinz, <a href="/A244165/b244165.txt">Table of n, a(n) for n = 2..400</a>
%p A244165 b:= proc(n, i, p, k) option remember; `if`(n=0, p!, `if`(i<1, 0,
%p A244165       add(b(n-i*j, i-1, p+j, k)/j!, j=[0, $max(1, k)..n/i])))
%p A244165     end:
%p A244165 a:= n-> b(n$2, 0, 2) -b(n$2, 0, 3):
%p A244165 seq(a(n), n=2..50);
%Y A244165 Column k=2 of A242451.
%K A244165 nonn
%O A244165 2,5
%A A244165 _Alois P. Heinz_, Jun 21 2014