

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
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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) 312.


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

## perioddoubling 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**(j1)), 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



