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A077772
Continued fraction expansion of the ternary Champernowne constant.
10
0, 1, 1, 2, 37, 1, 162, 1, 1, 1, 3, 1, 7, 1, 9, 2, 3, 1, 3068518062211324, 2, 1, 2, 6, 13, 1, 2, 1, 3, 1, 10, 1, 21, 1, 1, 4, 3, 577, 1, 1079268324684171943515797470873767312825026176345571319042096689270, 1, 1, 1, 3, 4, 21, 3, 1, 9, 1
OFFSET
0,4
LINKS
John K. Sikora, Table of n, a(n) for n = 0..2061 (terms n = 0..1155 from Robert G. Wilson v)
Eric Weisstein's World of Mathematics, Ternary Champernowne Constant
MATHEMATICA
almostNatural[n_, b_] := Block[{m = 0, d = n, i = 1, l, p}, While[m <= d, l = m; m = (b - 1) i*b^(i - 1) + l; i++]; i--; p = Mod[d - l, i]; q = Floor[(d - l)/i] + b^(i - 1); If[p != 0, IntegerDigits[q, b][[p]], Mod[q - 1, b]]]; Take[ ContinuedFraction[ FromDigits[ {Array[almostNatural[#, 3] &, 20000], 0}, 3]], 100] (* Robert G. Wilson v, Jul 21 2014 *)
PROG
(PARI) \p 10000
t=0; r=0.; T=1; for(n=1, 1e6, d=#digits(n, 3); t+=d; T*=3^d; r+=n/T; if(t>20959, return)); v=contfrac(r); v[1..30] \\ Charles R Greathouse IV, Sep 23 2014
(PARI) A077772(b=3, t=1., s=b)={contfrac(sum(n=1, default(realprecision)*2.303/log(b)+1, n<s||s*=b; n*t/=s))} \\ First optional arg allows us to get the c.f. of C[b] for other bases. - M. F. Hasler, Oct 25 2019
CROSSREFS
Cf. A054635 (ternary digits), A077771 (decimals).
Cf. A030190, A066716, A066717: binary digits, decimals and continued fraction of the binary Champernowne constant; A033307: decimal Champernowne constant.
Sequence in context: A358972 A073581 A078081 * A083150 A066146 A258035
KEYWORD
nonn,base,cofr
AUTHOR
Eric W. Weisstein, Nov 15 2002
STATUS
approved