cp's OEIS Frontend

A064010 Numbers k such that sopf(k) = d(k) where d(k) = A001223(k) and sopf(k) = A008472(k).

%I A064010 #17 Jun 22 2018 04:44:02
%S A064010 2,64,135,154,168,256,350,512,539,1029,1350,1875,2106,2268,2646,2673,
%T A064010 2736,2976,4375,6000,6076,6517,6880,7680,9680,10092,10584,14000,14406,
%U A064010 14580,14976,17500,18522,20412,26000,26068,26112,26620,27216,28812
%N A064010 Numbers k such that sopf(k) = d(k) where d(k) = A001223(k) and sopf(k) = A008472(k).
%H A064010 Giovanni Resta, <a href="/A064010/b064010.txt">Table of n, a(n) for n = 1..2000</a> (first 150 terms from Harry J. Smith)
%o A064010 (PARI) sopf(n,s,fac,i)=fac=factor(n); for(i=1,matsize(fac)[1], s=s+fac[i,1]); return(s);
%o A064010 d(n) = prime(n+1)-prime(n);
%o A064010 j=[]; for(n=1,50000, if(sopf(n)==d(n),j=concat(j,n))); j
%o A064010 (PARI) sopf(n)= { local(f,s=0); f=factor(n); for(i=1, matsize(f)[1], s+=f[i, 1]); return(s) }
%o A064010 d(n)= { prime(n + 1) - prime(n) }
%o A064010 { default(primelimit, 13500000); n=0; for (m=1, 10^9, if (sopf(m)==d(m), write("b064010.txt", n++, " ", m); if (n==150, break)) ) } \\ _Harry J. Smith_, Sep 05 2009
%Y A064010 Cf. A001223, A008472.
%K A064010 easy,nonn
%O A064010 1,1
%A A064010 _Jason Earls_, Sep 07 2001