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A106155
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Numbers k > 2 such that prime(k)# + (prime(k+1))^2 or prime(k+1)# - (prime(k+2))^2 is prime or both are primes.
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1
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3, 4, 5, 6, 7, 10, 12, 13, 19, 26, 28, 41, 66, 73, 76, 78, 85, 371, 437, 513, 661, 726, 924, 1063, 1331, 1380, 1422, 1602, 1947, 1963, 3091, 3295, 3401
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OFFSET
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1,1
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LINKS
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EXAMPLE
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2*3*5 + 7*7 = 79 prime as 2*3*5*7 - 11*11 = 89 prime so a(1)=3.
2*3*5*7 + 11*11 = 331 prime as 2*3*5*7*11 -13*13 = 2141 prime so a(2)=4.
2*3*5*7*11 + 13*13 = 2479 = 37*67 composite.
2*3*5*7*11*13 - 17*17 = 29471 prime so a(3)=5.
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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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EXTENSIONS
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STATUS
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approved
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