%I #10 Jan 10 2019 02:20:59
%S 1,2,3,2,5,6,7,2,3,10,11,6,13,14,15,2,17,6,19,10,21,22,23,6,5,26,3,14,
%T 29,900,31,2,33,34,35,6,37,38,39,10,41,1764,43,22,15,46,47,6,7,10,51,
%U 26,53,6,55,14,57,58,59,900,61,62,21,2,65,4356,67,34,69,4900,71,6,73,74,15
%N Product of the nonzero elements of the n-th row of A166139.
%C Differs from A007947 at n = 30.
%p A080305 := proc(n) if numtheory[mobius](n) < 0 then n; else 1; end if; end proc:
%p A126988 := proc(n,k) if n mod k = 0 then n/k ; else 0; end if; end proc:
%p A166139 := proc(n,k) A080305(A126988(n,k)) ; end proc:
%p A166140 := proc(n) a := 1 ; for k from 1 to n do if n mod k = 0 then a := a* A166139(n,k) ; end if; end do: a ; end proc:
%p seq(A166140(n),n=1..75) ; # _R. J. Mathar_, May 30 2011
%t A080305[n_]:= If[MoebiusMu[n]<0,n,1];
%t A126988[n_,k_]:=If[Mod[n, k]==0, n/k, 0];
%t A166139[n_,k_]:=A080305[A126988[n,k]];
%t A166140[n_]:= (p=1; For[k=1, k<n, k++, If[Mod[n,k]==0, p*=A166139[n,k]]]; p)
%t Table[A166140[n], {n,100}] (* _Jon Maiga_, Jan 10 2019 *)
%Y Cf. A166139, A014963.
%K nonn
%O 1,2
%A _Mats Granvik_, Oct 08 2009