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Search: id:A093429
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%I A093429
%S A093429 1,1,1,1,2,2,2,3,2,3,2,2,3,2,2,4,3,2,6,3,4,4,3,1,1,3,3,3,3,2,4,3,3,3,3,
%T A093429 5,4,2,3,3,5,3,7,4,1,4,4
%N A093429 Number of distinct prime factors of (p[1]*...*p[n])+(p[n+1]*...*p[2n]), 
               where p[n] is the n-th prime.
%C A093429 Prime for n=1,2,3,4,24,25,45,59 and no more for n<100.
%H A093429 Dario Alejandro Alpern, <a href="http://www.alpertron.com.ar/ECM.HTM">
               Factorization using the Elliptic Curve Method</a>.
%H A093429 P. Samidoost, <a href="http://groups.yahoo.com/group/primenumbers/message/
               14849">Primenumbers group posting</a>.
%e A093429 a(31)=4 because 509102378439545188849067644696085192959414195658632710736111053092210207
%e A093429 = 3711597629 * 238694867020723 * 226814268663739929299 * 2533557617597929944840907379.
%t A093429 PrimeFactors[n_] := Flatten[ Table[ # [[1]], {1} ] & /@ FactorInteger[n]]; 
               f[n_] := Length[ PrimeFactors[ Product[Prime[i], {i, n}] + Product[Prime[i 
               + n], {i, n}]]]; Table[ f[n], {n, 20}]
%Y A093429 Sequence in context: A058013 A031356 A024676 this_sequence A089842 A071215 
               A164024
%Y A093429 Adjacent sequences: A093426 A093427 A093428 this_sequence A093430 A093431 
               A093432
%K A093429 nonn
%O A093429 1,5
%A A093429 Jason Earls (zevi_35711(AT)yahoo.com), May 12 2004
%E A093429 a(40) - a(48) from Robert G. Wilson v (rgwv(AT)rgwv.com), May 27 2004

    
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Last modified December 17 13:29 EST 2009. Contains 170826 sequences.


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