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A118561
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Lucky numbers for which the reversal is also a lucky number.
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4
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1, 3, 7, 9, 13, 15, 31, 33, 37, 51, 73, 99, 111, 115, 133, 141, 151, 163, 169, 171, 189, 193, 195, 303, 327, 331, 339, 361, 385, 391, 393, 399, 511, 529, 535, 537, 579, 583, 591, 717, 723, 727, 729, 735, 739, 777, 787, 925, 927, 933, 937, 961, 975, 979, 981, 993
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OFFSET
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1,2
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LINKS
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EXAMPLE
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133 is in the sequence because (1) it is a lucky number and (2) the reversal 331 is also a lucky number.
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MATHEMATICA
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nn = 10^3; t = Range[1, nn, 2]; sieve[n_] := Module[{k = t[[n]]}, t = Delete[t, Table[{i}, {i, k, Length[t], k}]]]; n = 1; While[t[[n]] < Length[t], n++; sieve[n]]; tr = Table[FromDigits[Reverse[IntegerDigits[i]]], {i, t}]; Intersection[t, tr] (* T. D. Noe, Mar 16 2013 *)
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CROSSREFS
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KEYWORD
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base,nonn
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AUTHOR
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Luc Stevens (lms022(AT)yahoo.com), May 07 2006
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EXTENSIONS
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Corrected and extended by Adam Panagos (adam.panagos(AT)gmail.com), May 10 2006
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STATUS
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approved
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