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A188195 Base-3 Keith numbers. 8
3, 5, 6, 7, 57, 102, 127, 206, 217, 677, 805, 840, 1486, 1680, 1887, 2090, 2834, 8329, 10145, 12866, 21127, 23002, 50782, 67925, 82685, 96841, 153861, 178852, 357896, 3826652, 17985694, 38610616, 38610808, 70587766, 160804168, 341014432, 632582224 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Keith numbers are described in A007629.

LINKS

Table of n, a(n) for n=1..37.

EXAMPLE

57 is here because, in base 3, 57 is 2010 and applying the Keith iteration to this number produces the numbers 2, 0, 1, 0, 3, 4, 8, 15, 30, 57.

MATHEMATICA

IsKeith[n_, b_] := Module[{d, s, k}, d = IntegerDigits[n, b]; s = Total[d]; k = 1; While[AppendTo[d, s]; s = 2 s - d[[k]]; s < n, k++]; s == n]; Select[Range[3, 10^5], IsKeith[#, 3]&]

CROSSREFS

Cf. A007629 (base 10), A162724 (base 2), A187713 (base 5), A188196-A188200.

Sequence in context: A072134 A179220 A145736 * A021741 A201906 A267158

Adjacent sequences:  A188192 A188193 A188194 * A188196 A188197 A188198

KEYWORD

nonn,base

AUTHOR

T. D. Noe, Mar 24 2011

STATUS

approved

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Last modified February 23 23:57 EST 2017. Contains 282560 sequences.