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A029962 Palindromic in bases 5 and 10. 15
0, 1, 2, 3, 4, 6, 88, 252, 282, 626, 676, 1221, 15751, 18881, 10088001, 10400401, 27711772, 30322303, 47633674, 65977956, 808656808, 831333138, 831868138, 836131638, 836181638, 2512882152, 2596886952, 2893553982, 6761551676 (list; graph; refs; listen; history; internal format)
OFFSET

1,3

LINKS

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, 5], AppendTo[l, a]], {n, 200000}]; l (from Robert G. Wilson v Sep 30 2004)

CROSSREFS

Cf. A007632, A007633, A029961, A029963, A029964, A029965, A029966, A029967, A029968, A029969, A029970.

Sequence in context: A084811 A051856 A135236 * A021903 A058315 A072717

Adjacent sequences:  A029959 A029960 A029961 * A029963 A029964 A029965

KEYWORD

nonn,base

AUTHOR

Patrick De Geest (pdg(AT)worldofnumbers.com)

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Last modified February 13 05:39 EST 2012. Contains 205436 sequences.