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A118561
Lucky numbers for which the reversal is also a lucky number.
4
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
OFFSET
1,2
LINKS
Amiram Eldar, Table of n, a(n) for n = 1..10000 (terms 1..9014 from T. D. Noe)
EXAMPLE
133 is in the sequence because (1) it is a lucky number and (2) the reversal 331 is also a lucky number.
MATHEMATICA
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 *)
CROSSREFS
Sequence in context: A120226 A137310 A118567 * A309406 A057701 A140291
KEYWORD
base,nonn
AUTHOR
Luc Stevens (lms022(AT)yahoo.com), May 07 2006
EXTENSIONS
Corrected and extended by Adam Panagos (adam.panagos(AT)gmail.com), May 10 2006
957 removed by T. D. Noe, Mar 16 2013
STATUS
approved