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Number of Carlitz compositions having at least two identical parts.
10

%I #15 Apr 30 2017 16:00:33

%S 0,0,0,0,1,2,3,10,20,44,67,149,277,528,959,1673,3107,5572,9992,17801,

%T 31647,55379,98445,173288,305355,536709,943353,1655316,2900221,

%U 5088098,8916905,15624332,27368888,47935241,83939143,146974040,257277523,450432510,788487147

%N Number of Carlitz compositions having at least two identical parts.

%H Alois P. Heinz, <a href="/A285981/b285981.txt">Table of n, a(n) for n = 0..4100</a>

%F a(n) = A003242(n) - A032020(n).

%e For n=7, there are a(7) = 10 Carlitz compositions with at least two identical parts: 1,5,1; 2,3,2; 3,1,3; 1,2,1,3; 1,2,3,1; 1,3,1,2; 1,3,2,1; 2,1,3,1; 3,1,2,1 and 1,2,1,2,1.

%Y Cf. A003242, A032020.

%K nonn

%O 0,6

%A _Gregory L. Simay_, Apr 29 2017

%E More terms from _Alois P. Heinz_, Apr 29 2017