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A056602
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Numbers A such that there is an equation of the form (A = Product of m + 1 primes) = (B = Product of m primes) + (C = Product of m primes), where A*B*C is a primorial number (A002110).
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2
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OFFSET
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1,1
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COMMENTS
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Terms have been verified. There are no additional terms for m <= 7. - Rick L. Shepherd, Jun 16 2008
(C(3m+1,m+1)*C(2m,m))/(C(3m-2,m)*C(2m-2,m-1)) = (27m^2-1)/(m^2+1), so for a brute-force search for large m, about 27 times as many cases must be examined for m as for m-1. - Rick L. Shepherd, Jun 16 2008
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LINKS
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EXAMPLE
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10 = (2*5) = 3+7;
231 = (3*7*11) = (2*5)+(13*17);
2958 = (2*3*17*29) = (5*13*23)+(7*11*19);
226083 = (3*11*13*17*31) = (2*7*19*23)+(5*29*37*41).
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CROSSREFS
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KEYWORD
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more,nonn
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AUTHOR
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STATUS
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approved
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