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%I #12 Feb 17 2018 11:54:54
%S 1,1,1,1,1,2,1,1,2,2,2,1,1,3,1,1,1,2,3,2,1,1,1,4,1,1,3,3,2,2,1,4,1,2,
%T 1,2,3,1,3,1,1,5,1,2,3,1,3,2,1,3,5,1,2,2,1,3,4,2,1,5,1,1,1,3,5,1,2,1,
%U 1,1,5,2,2,4,3,3,3,1,5,3,1,4,3,1,2,2,1,1,7,1,1,1,2,1,5,3,1,3,5,1,1,3,3,3,5
%N Number of ways A002808(n) can be properly factored into 2 integers.
%H Robert Israel, <a href="/A033941/b033941.txt">Table of n, a(n) for n = 1..10000</a>
%p f:= proc(t) if not isprime(t) then (numtheory:-tau(t) +`if`(issqr(t), 1, 0))/2 - 1 fi end proc:
%p map(f, [$4..1000]); # _Robert Israel_, Feb 15 2018
%o (PARI) f(n) = (numdiv(n) + issquare(n))/2 - 1;
%o lista(nn) = forcomposite(n=1, nn, print1(f(n), ", ")) \\ _Michel Marcus_, Feb 16 2018
%K nonn
%O 1,6
%A _Jeff Burch_
%E Corrected by _Robert Israel_, Feb 15 2018
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