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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

User: Carlo Carminati

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Carlo Carminati has authored 1 sequences.

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....

Original entry on oeis.org

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
Offset: 0

Author

Carlo Carminati, Mar 03 2011

Keywords

Comments

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

Crossrefs

Cf. A026465.

Programs

  • 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)];
  • Mathematica
    First[RealDigits[FromContinuedFraction[ThueMorse[Range[550]]] - 1, 10, 100]] (* Paolo Xausa, Apr 04 2024 *)