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A047813 Largest palindromic substring of n. 7
0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 1, 11, 2, 3, 4, 5, 6, 7, 8, 9, 2, 2, 22, 3, 4, 5, 6, 7, 8, 9, 3, 3, 3, 33, 4, 5, 6, 7, 8, 9, 4, 4, 4, 4, 44, 5, 6, 7, 8, 9, 5, 5, 5, 5, 5, 55, 6, 7, 8, 9, 6, 6, 6, 6, 6, 6, 66, 7, 8, 9, 7, 7, 7, 7, 7, 7, 7, 77, 8, 9, 8, 8, 8, 8, 8, 8, 8, 8, 88, 9, 9, 9, 9, 9, 9, 9 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

COMMENTS

a(n) = A262188(n,A262190(n)-1). - Reinhard Zumkeller, Sep 14 2015

LINKS

Reinhard Zumkeller, Table of n, a(n) for n = 0..10000

Index entries for sequences related to palindromes

EXAMPLE

a(1313) = Max{1,3,131,313} = 313.

MATHEMATICA

palQ[n_Integer, base_Integer] := Module[{idn = IntegerDigits[n, base]}, idn == Reverse[ idn]]; f[n_] := Block[{id = IntegerDigits@ n, mx = -Infinity}, k = Length@ id; While[k > 0 && mx == -Infinity, mx = Max[mx, Select[ FromDigits@# & /@ Partition[id, k, 1], palQ[#, 10] &]]; k--]; mx] (* Robert G. Wilson v, Aug 24 2011 *)

lps[n_]:=Module[{idn=IntegerDigits[n]}, Max[FromDigits/@Select[ Flatten[ Table[ Partition[ idn, i, 1], {i, Length[idn]}], 1], #==Reverse[#]&]]]; Array[ lps, 100, 0] (* Harvey P. Dale, Jan 09 2015 *)

PROG

(Haskell)

a047813 = last . a262188_row

-- Reinhard Zumkeller, Sep 14 2015, Aug 23 2011

CROSSREFS

Cf. A136522.

Cf. A262188, A262223, A262224.

Sequence in context: A052500 A179933 A259433 * A084051 A069652 A055483

Adjacent sequences:  A047810 A047811 A047812 * A047814 A047815 A047816

KEYWORD

nonn,easy,base,nice,look

AUTHOR

N. J. A. Sloane

STATUS

approved

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Last modified February 17 23:47 EST 2018. Contains 299297 sequences. (Running on oeis4.)