A032640 Numbers k such that k concatenated with itself is a lucky number.

3, 9, 21, 23, 51, 59, 63, 71, 75, 87, 89, 99, 105, 111, 117, 123, 129, 135, 143, 147, 153, 171, 173, 177, 191, 201, 237, 243, 255, 263, 285, 305, 309, 317, 327, 357, 363, 369, 371, 387, 389, 393, 431, 443, 459, 465, 467, 495, 497, 513, 521, 533, 561, 567, 573

Offset

1,1

Links

Kevin P. Thompson, Table of n, a(n) for n = 1..4215 (first 95 terms from Amiram Eldar)

Example

123 is a member of the sequence since 123123 is a lucky number, i.e. A000959(10590) = 123123.

Crossrefs

Cf. A000959, A032650.

Sequence in context: A109612 A032668 A050839 * A245202 A127174 A251535

Adjacent sequences: A032637 A032638 A032639 * A032641 A032642 A032643

Keyword

nonn,base

Author

Patrick De Geest, May 15 1998

Extensions

More terms from Sascha Kurz, Mar 24 2002

Status

approved