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A176274
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Numbers of the form 3k-1 with greatest prime divisor of the form 3m+1
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3
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14, 26, 35, 38, 56, 62, 65, 74, 86, 95, 98, 104, 122, 134, 140, 143, 146, 152, 155, 158, 182, 185, 194, 206, 209, 215, 218, 224, 245, 248, 254, 260, 266, 278, 296, 302, 305, 314, 323, 326, 335, 338, 341, 344, 350, 362, 365, 380, 386, 392, 395, 398, 407, 416, 422, 434, 446
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OFFSET
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1,1
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COMMENTS
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All numbers of the form 2p, where p==1(mod 3) is prime, are in the sequence.
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LINKS
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MATHEMATICA
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Select[Range[500], Divisible[#+1, 3]&&Divisible[FactorInteger[#] [[-1, 1]]-1, 3]&] (* Harvey P. Dale, Jul 29 2019 *)
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PROG
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(PARI) isok(n) = ((n % 3) == 2) && ((vecmax(factor(n)[, 1]) % 3) == 1); \\ Michel Marcus, Feb 08 2016
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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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