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A263108
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Semiprimes m such that the leftward cyclic permutation of its decimal digits is a larger semiprime.
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1
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15, 26, 39, 49, 58, 122, 129, 134, 141, 145, 155, 158, 159, 161, 177, 178, 183, 185, 187, 226, 254, 262, 298, 339, 341, 355, 358, 362, 371, 381, 391, 393, 394, 445, 451, 469, 473, 493, 497, 565, 581, 583, 586, 589, 674, 781, 791, 889, 895, 899, 1114, 1119
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OFFSET
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1,1
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COMMENTS
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LINKS
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EXAMPLE
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Permute the digits of 15 = 3 * 5 to get 51 = 3 * 17.
Permute the digits of 26 = 2 * 13 to get 62 = 2 * 31.
Permute the digits of 122 = 2 * 61 to get 221 = 13 * 17.
Permute the digits of 129 = 3 * 43 to get 291 = 3 * 97.
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MATHEMATICA
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Select[Range[4, 1000000], 2 == PrimeOmega[#] == PrimeOmega[fd = FromDigits[RotateLeft[IntegerDigits[#]]]] && fd > # &] (* for b-file *)
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CROSSREFS
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KEYWORD
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nonn,base
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AUTHOR
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STATUS
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approved
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