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%I #5 Mar 30 2012 18:39:02
%S 0,0,0,1,1,1,1,1,2,2,2,2,2,2,2,3,3,3,3,3,4,4,4,4,5,5,6,6,6,6,6,6,6,6,
%T 6,6,6,6,6,6,6,6,6,6,6,6,6,6,7,7,7,7,7,7,7,7,8,8,8,8,8,8,8,8,8,8,8,8,
%U 8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9
%N Number of pairs (x,y) such that tau(x^y) = x+y, 1<=x<=n, 1<=y<=n.
%o (PARI) for(n=1,130,print1(sum(i=1,n,sum(j=1,n,if(numdiv(i^j)-i-j,0,1))),","))
%Y Cf. A000005.
%K nonn
%O 1,9
%A _Benoit Cloitre_, Jun 06 2002
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