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A257315
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a(1) = 34; a(2) = 35; for n > 2, a(n) is the smallest number of the form prime + 32 not already used which shares a factor with a(n-1).
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7
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34, 35, 45, 39, 51, 63, 49, 91, 105, 55, 75, 69, 93, 99, 111, 37, 259, 133, 171, 129, 43, 301, 189, 135, 85, 115, 145, 195, 141, 159, 183, 61, 793, 169, 273, 213, 225, 205, 255, 231, 121, 363, 243, 261, 303, 309, 103, 1339, 325, 265, 295, 315, 339, 345, 369
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OFFSET
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1,1
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COMMENTS
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Analog of EKG-sequence (A064413) on the numbers of the form prime + 32.
Conjecture: the sequence {a(n)-32} is a permutation of primes (A000040).
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LINKS
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MATHEMATICA
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f[n_] := Block[{o = 2^5, s, p, k}, s = {o + 2, o + 3}; For[k = 3, k <= n, k++, p = 2; While[GCD[p + o, s[[k - 1]]] == 1 || MemberQ[s, p + o], p = NextPrime@ p]; AppendTo[s, p + o]]; s]; f@ 55 (* Michael De Vlieger, Apr 20 2015 *)
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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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