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%I #19 Nov 17 2019 03:50:47
%S 5,15,77,99,104,153,369,492,539,714,1330,2491,4191,5405,5831,5959,
%T 6556,6579,6723,8463,9424,12221,12351,12726,13419,14587,21716,24432,
%U 24880,24895,26642,30267,31487,33019,35456,38324,43215,43802,44831,45524
%N Numbers k such that sopf(k) = sopfr(k+1), where sopf(k) = A008472(k) and sopfr(k) = A001414(k).
%H Amiram Eldar, <a href="/A064678/b064678.txt">Table of n, a(n) for n = 1..10000</a> (terms 1..500 from Harry J. Smith)
%o (PARI) sopf(n)= { local(f,s=0); f=factor(n); for(i=1, matsize(f)[1], s+=f[i, 1]); return(s) } sopfr(n)= { local(f,s=0); f=factor(n); for(i=1, matsize(f)[1], s+=f[i, 1]*f[i, 2]); return(s) } { n=0; for (m=1, 10^9, if (sopf(m)==sopfr(m + 1), write("b064678.txt", n++, " ", m); if (n==500, break)) ) } \\ _Harry J. Smith_, Sep 22 2009
%Y Cf. A001414 (sopfr), A008472 (sopf).
%K easy,nonn
%O 1,1
%A _Jason Earls_, Oct 10 2001
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