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A187061 Digits of the decimal expansion the constant whose continued fraction expansion is given by (a suffix of) A026465 (just start from the second term): [0;2,1,1,2,2,2,1,1,2,1,1,...]=0.3867499707.... 0
3, 8, 6, 7, 4, 9, 9, 7, 0, 7, 1, 4, 3, 0, 0, 7, 0, 6, 1, 7, 1, 5, 2, 4, 8, 0, 3, 4, 8, 5, 5, 8, 0, 9, 3, 9, 6, 6, 1, 4, 4, 7, 6, 1, 5, 5, 6, 3, 0, 7, 7, 5, 0, 5, 1, 4, 7, 5, 0, 2, 8, 0, 5, 6, 8, 1, 2, 2, 4, 0, 7, 0, 7, 5, 8, 0, 5, 2, 9, 0, 9, 1 (list; constant; graph; refs; listen; history; text; internal format)
OFFSET

0,1

COMMENTS

Since the continued fraction of 0.3867499707... is a sequence which is the fixed point of a substitution, this constant is transcendental.

REFERENCES

J. Cassaigne, Limit values of the recurrence quotient of Sturmian sequences, Theoret. Comput. Sci. 218 (1999) 3-12.

LINKS

Table of n, a(n) for n=0..81.

Claudio Bonanno, Carlo Carminati, Stefano Isola, Giulio Tiozzo, Dynamics of continued fractions and kneading sequences of unimodal maps, arXiv:1012.2131

MAPLE

## period-doubling routine (see A026465):

double:=proc(SS)

NEW:=[op(S), op(S)]:

if op(nops(NEW), NEW)=1

then NEW:=[seq(op(j, NEW), j=1..nops(NEW)-2), op(nops(NEW)-1, NEW)+1]:

else NEW:=[seq(op(j, NEW), j=1..nops(NEW)-1), op(nops(NEW)-1, NEW)-1, 1]:

fi:

end proc:

# 10 loops of the above routine generate the first 1365 terms of the sequence

S:=[2]:

for j from 1 to 10  do S:=double(S); od:

## transform the list S into a continued fraction:

Digits:=500;

with(numtheory);

q:=evalf(invcfrac([[0], S]));

## list of digits:

L:=[seq(floor(q*10**j) - 10*floor(q*10**(j-1)), j=1..200)];

CROSSREFS

Cf. A026465

Sequence in context: A106291 A137987 A212007 * A020809 A152683 A154199

Adjacent sequences:  A187058 A187059 A187060 * A187062 A187063 A187064

KEYWORD

nonn,cons,easy

AUTHOR

Carlo Carminati, Mar 03 2011

STATUS

approved

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Last modified February 21 14:40 EST 2018. Contains 299414 sequences. (Running on oeis4.)