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%I #14 Jun 21 2018 02:00:00
%S 15012,124956,128412,135972,186732,219520,241812,377892,414180,420660,
%T 447876,453060,453492,497772,504036,515052,523044,528876,544212,
%U 658560,776412,826956,1009792,1020060,1135836,1191132,1425060,1467180,1511892
%N Numbers whose sum of nonunitary divisors and sum of unitary divisors are both positive squares.
%H Harry J. Smith, <a href="/A064730/b064730.txt">Table of n, a(n) for n = 1..750</a>
%o (PARI) {usigma(n, s=1, fac, i) = fac=factor(n); for(i=1,matsize(fac)[1],s=s*(1+fac[i,1]^fac[i,2])); return(s); } nu(n) = sigma(n)-usigma(n); for(n=1,10^8, if(nu(n)>0 && issquare(nu(n)) && issquare(usigma(n)), print1(n,",")))
%o (PARI) usigma(n)= { local(f,s=1); f=factor(n); for(i=1, matsize(f)[1], s*=1 + f[i, 1]^f[i, 2]); return(s) } { n=0; for (m = 1, 10^9, u=usigma(m); nu=sigma(m) - u; if (nu>0 && issquare(nu) && issquare(u), write("b064730.txt", n++, " ", m); if (n==750, break)) ) } \\ _Harry J. Smith_, Sep 24 2009
%Y Cf. A034448, A048146.
%K nonn
%O 1,1
%A _Jason Earls_, Oct 17 2001
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