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A105587 Row sums of a Möbius-binomial triangle. 1

%I #8 Dec 24 2015 02:45:29

%S 1,2,3,4,1,6,7,8,2,3,11,12,4,14,15,16,5,18,6,20,7,22,23,24,8,9,27,10,

%T 11,30,31,32,12,34,35,36,13,38,39,40,14,42,43,44,15,16,47,48,17,18,19,

%U 52,20,54,21,56,22,58,59,60,23,62,63,24,25,66,67,68,26,70,71,72,27,74,75

%N Row sums of a Möbius-binomial triangle.

%C a(n) = n unless n is nonsquarefree, in which case a(n) = rank of n as a nonsquarefree number. Row sums of A105586.

%F a(n) = Sum_{k=0..n} binomial(abs(mu(n)), abs(mu(k))).

%e a(4) = 1 since 4 is the first nonsquarefree number;

%e a(8) = 2 since 8 is the second nonsquarefree number.

%K easy,nonn

%O 0,2

%A _Paul Barry_, Apr 14 2005

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