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A109068
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Products of two successive primes that can be partitioned in sum of three distinct primes which contain the prime divisors.
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0
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15, 35, 77, 221, 899, 1517, 2021, 5183, 8633, 11663, 23707, 27221, 36863, 41989, 47053, 57599, 60491, 77837, 111547, 164009, 233273, 324899, 372091, 416021, 471953, 522713, 568507, 608351, 665831, 680621
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OFFSET
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1,1
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COMMENTS
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Largest prime of sum of three primes are primes of the form p*q - p - q, where p and q are two successive primes (A096345).
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LINKS
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FORMULA
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EXAMPLE
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a(1) = 15 because 15 = 3+5+7 with 3*5 =15;
a(2) = 35 because 35 = 5+7+23 with 5*7=35;
a(3) = 77 because 77 = 7+11+59 with 7*11=77;
a(4) = 221 because 221= 13+17+191 with 13*17=221
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PROG
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(PARI) lista(nn) = {for (n=1, nn, p = prime(n); q = prime(n+1); prd = p*q; if (isprime(prd - p - q), print1(prd, ", ")); ); } \\ Michel Marcus, Jun 03 2013
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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