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%I #12 Apr 11 2021 23:39:37
%S 5,39,172,305,1182,1194,2947,8936,24363,24399,24417,64730,174977,
%T 482028,9559785,9559905,25876016,25876976,70113457,189965322,
%U 189967014,189967122,189967266,189968202,1394198020,3779850963,3779851593
%N Numbers k such that sopf(k) - pi(k) = tau(k).
%e 5 is in the sequence since sopf(5) - pi(5) = 5 - 3 = 2 = tau(5).
%o (PARI) sopf(n, fac) = fac=factor(n); sum(i=1,matsize(fac)[1],fac[i,1]); pi(x, c) = forprime(p=2,x,c++); c for(n=1,10^6, if(sopf(n)-pi(n)==numdiv(n),print(n)))
%Y Cf. A000005 (tau), A000720 (pi), A008472 (sopf).
%K nonn
%O 1,1
%A _Jason Earls_, Oct 02 2001
%E More terms from _Klaus Brockhaus_, Oct 05 2001. No further term < 800000.
%E Corrected offset and a(15)-a(27) from _Donovan Johnson_, Mar 10 2010
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