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A329254 Smallest palindrome k, not less than n, such that k is also a palindrome in base n. 1
1, 3, 4, 5, 6, 7, 8, 9, 191, 11, 232, 181, 222, 323, 828, 353, 252, 171, 666, 252, 22, 161, 737, 525, 494, 989, 252, 232, 929, 434, 1551, 33, 272, 525, 252, 111, 494, 585, 5775, 656, 252, 989, 44, 585, 414, 141, 2112, 343, 3333, 969, 676, 212, 5885, 55, 616 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

a(10^k) = 10^k+1 for k > 0. Conjecture: a(n) in base n has 3 or fewer digits. - Chai Wah Wu, Nov 17 2019

LINKS

Chai Wah Wu, Table of n, a(n) for n = 1..10000

EXAMPLE

For n=9, 191_10 = 232_9.

MATHEMATICA

Flatten@{1, Table[k = n; While[! PalindromeQ[k] || k != IntegerReverse[k, n], k++ ]; k, {n, 2, 200}]}

PROG

(PARI) ispal(k, b) = { my(d=digits(k, b)); d == Vecrev(d); }

a(n) = {if (n == 1, return(1)); my(k=n); while (!ispal(k, 10) || ! ispal(k, n), k++); k; } \\ Michel Marcus, Nov 18 2019

CROSSREFS

Cf. A002113 (palindromes in base 10).

Sequence in context: A037351 A293727 A077528 * A183296 A138928 A116587

Adjacent sequences:  A329251 A329252 A329253 * A329255 A329256 A329257

KEYWORD

nonn,base

AUTHOR

Robert Price, Nov 09 2019

STATUS

approved

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Last modified May 27 02:41 EDT 2022. Contains 354093 sequences. (Running on oeis4.)