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Column 1 of triangle A117170 of Inverse-Shift-Moebius coefficients and so equals the Inverse-Shift-Moebius transform of [1,0,0,0,...].
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%I #5 Mar 30 2012 18:37:44

%S 1,1,2,2,3,3,4,3,6,5,5,6,7,7,10,7,8,10,11,11,14,11,11,14,16,14,18,17,

%T 17,21,18,17,23,22,24,25,21,24,32,28,27,33,28,32,39,30,31,36,38,41,42,

%U 41,38,50,48,44,48,45,46,59,49,53,65,55,59,63,56,65,71,70,61,72,62,72,84

%N Column 1 of triangle A117170 of Inverse-Shift-Moebius coefficients and so equals the Inverse-Shift-Moebius transform of [1,0,0,0,...].

%o (PARI) {a(n)=if(n<1,0,prod(i=0,n, matrix(n,n,r,c,if(r>=c,if((r+i)%(c+i)==0,1,0))))[n,1])}

%Y Cf. A117170 (triangle), A117172 (column 2), A117173 (column 3), A117174 (row sums).

%K nonn

%O 1,3

%A _Wouter Meeussen_ and _Paul D. Hanna_, Mar 05 2006