A118561 - OEIS

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A118561

Lucky numbers for which the reversal is also a lucky number.

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

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,2

LINKS

Amiram Eldar, Table of n, a(n) for n = 1..10000 (terms 1..9014 from T. D. Noe)

W. Schneider, The First 1,000 Lucky Number.

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

Cf. A000959, A309406.

Sequence in context: A120226 A137310 A118567 * A309406 A057701 A140291

Adjacent sequences: A118558 A118559 A118560 * A118562 A118563 A118564

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