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%I #23 Feb 03 2020 03:49:53
%S 2,3,7,5,11,110,71,722,359,329902,39916801,2834342,75024430,
%T 3790360510,46271879,1059865,1538931,123611150,1713311273363902,
%U 117897322430,2703876255255,93799610095770191,148139754736864717
%N Sum of distinct primes dividing n! + 1.
%H Amiram Eldar, <a href="/A064011/b064011.txt">Table of n, a(n) for n = 1..139</a> (terms 1..60 from Harry J. Smith)
%F a(n) = A008472(A038507(n)). - _Amiram Eldar_, Feb 03 2020
%e a(6) = 110 since 6! + 1 = 721 = 7 * 103 and 7 + 103 = 110.
%t sopf[n_] := Plus @@ First @ Transpose @ FactorInteger[n]; sopf /@ Table[n! + 1 ,{n, 1, 23}] (* _Amiram Eldar_, Feb 03 2020 *)
%o (PARI) sopf(n,s,fac,i)=fac=factor(n); for(i=1,matsize(fac)[1], s=s+fac[i,1]); return(s);
%o for(n=1,23,print(sopf(n!+1)))
%o (PARI) sopf(n)= { local(f,s=0); f=factor(n); for(i=1, matsize(f)[1], s+=f[i, 1]); return(s) }
%o { for (n=1, 60, write("b064011.txt", n, " ", sopf(n! + 1)) ) } \\ _Harry J. Smith_, Sep 06 2009
%Y Cf. A008472, A038507.
%K nonn
%O 1,1
%A _Jason Earls_, Sep 07 2001
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