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A029970 Palindromic in bases 10 and 15. 15
0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 11, 828, 858, 888, 919, 949, 979, 1551, 2772, 23632, 25552, 60106, 67576, 465564, 477774, 489984, 515515, 527725, 17577571, 26144162, 28300382, 39399393, 47999974, 69455496, 2118008112, 8050880508 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

LINKS

Table of n, a(n) for n=1..36.

P. De Geest, Palindromic numbers beyond base 10

MATHEMATICA

NextPalindrome[n_] := Block[{l = Floor[ Log[10, n] + 1], idn = IntegerDigits[n]}, If[ Union[idn] == {9}, Return[n + 2], If[l < 2, Return[n + 1], If[ FromDigits[ Reverse[ Take[idn, Ceiling[l/2]] ]] FromDigits[ Take[idn, -Ceiling[l/2]]], FromDigits[ Join[ Take[idn, Ceiling[l/2]], Reverse[ Take[idn, Floor[l/2]] ]]], idfhn = FromDigits[ Take[idn, Ceiling[l/2]]] + 1; idp = FromDigits[ Join[ IntegerDigits[idfhn], Drop[ Reverse[ IntegerDigits[idfhn]], Mod[l, 2]] ]]] ]]]; palQ[n_Integer, base_Integer] := Block[{idn = IntegerDigits[n, base]}, idn == Reverse[idn]]; l = {0}; a = 0; Do[a = NextPalindrome[a]; If[ palQ[a, 15], AppendTo[l, a]], {n, 200000}]; l (from Robert G. Wilson v Sep 03 2004)

CROSSREFS

Cf. A007632, A007633, A029961, A029962, A029963, A029964, A029804, A029965, A029966, A029967, A029968, A029969, A029731, A097855, A099165.

Sequence in context: A097855 A029969 A029731 * A143265 A109841 A174234

Adjacent sequences:  A029967 A029968 A029969 * A029971 A029972 A029973

KEYWORD

nonn,base

AUTHOR

Patrick De Geest

STATUS

approved

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Last modified October 25 09:31 EDT 2014. Contains 248518 sequences.