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A248753 Palindromes p = A002113(n) whose index n is a substring of p. 1
11, 1111, 12221, 23332, 34443, 45554, 56665, 67776, 78887, 89998, 101101, 111111, 121121, 131131, 141141, 151151, 161161, 171171, 181181, 191191, 1020201, 1121211, 1222221, 1323231, 1424241, 1525251, 1626261, 1727271, 1828281, 1929291, 2030302, 2131312 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

That is to say the 'n' of A002113(n) is a substring of A002113(n).

LINKS

Table of n, a(n) for n=1..32.

EXAMPLE

11 is a term because the eleventh palindrome is 11.

12221 is in the sequence because the 222nd palindrome is 12221.

101101 is a member because it is the 1101st palindrome.

MATHEMATICA

(* first load 'nthPalindrome' from A002113 and then *) nPal[n_] := nthPalindrome[n - 1]; fQ[n_] := StringPosition[ ToString[ nPal[ n]], ToString[ n]] != {}; k = 1; lst = {}; While[k < 3001, If[fQ[k], AppendTo[lst, nPal[ k]]]; k++]; lst

CROSSREFS

Cf. A002113, A248754.

Sequence in context: A290067 A289934 A289968 * A248754 A099814 A260077

Adjacent sequences:  A248750 A248751 A248752 * A248754 A248755 A248756

KEYWORD

nonn,base,easy

AUTHOR

Robert G. Wilson v, Oct 13 2014

STATUS

approved

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Last modified June 2 08:16 EDT 2020. Contains 334767 sequences. (Running on oeis4.)