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A307882
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Records of the offset k in A307881, divided by 3.
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1
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-1, 1, 3, 5, 7, 9, 11, 13, 15, 25, 29, 31, 39, 45, 61, 63, 75, 81, 85, 111, 123, 131, 151, 175, 207, 225, 241, 267, 301, 329, 335, 427, 435, 505, 539, 565, 611, 617, 665, 695, 739, 805, 843, 875, 1113, 1143, 1465, 1797, 1801, 1959, 2065, 2369, 2783
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OFFSET
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1,3
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COMMENTS
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The divisibility of k by 3 of all terms after a(1) is conjectural. Offsets not divisible by 3 are given as -k instead of k/3.
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LINKS
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PROG
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(PARI) kmax=0; for(n=2, 10^7, forstep(k=1, n, 2, if(isprime(2*n-k)&&isprime(2*n+k), if(k>kmax, if(k%3!=0, print1(-k, ", "), print1(k/3, ", ")); kmax=k); break(1))))
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CROSSREFS
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KEYWORD
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sign,more
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AUTHOR
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STATUS
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approved
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