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A056544
Smallest palindrome containing the digits of n as a subsequence.
3
1, 2, 3, 4, 5, 6, 7, 8, 9, 101, 11, 121, 131, 141, 151, 161, 171, 181, 191, 202, 121, 22, 232, 242, 252, 262, 272, 282, 292, 303, 131, 232, 33, 343, 353, 363, 373, 383, 393, 404, 141, 242, 343, 44, 454, 464, 474, 484, 494, 505, 151, 252, 353, 454, 55, 565, 575
OFFSET
1,2
LINKS
FORMULA
a(A002113(n)) = A002113(n). - Chai Wah Wu, Apr 13 2021
EXAMPLE
The smallest palindrome containing 21 as a subsequence is 121. So a(21) = 121.
MATHEMATICA
Do[k = 1; While[ StringPosition[ ToString[k], ToString[n]] == {} || ToString[k] != StringReverse[ ToString[k]], k++ ]; Print[k], {n, 1, 70} ]
PROG
(PARI) See Links section.
CROSSREFS
Cf. A002113, A082216, A145800 (binary variant).
Sequence in context: A135295 A122625 A347400 * A082216 A052426 A240237
KEYWORD
base,easy,nonn
AUTHOR
Joseph L. Pe, Feb 10 2002
EXTENSIONS
Edited and extended by Robert G. Wilson v, Feb 12 2002
STATUS
approved