A110812 Fractalization of sqrt(2).

1, 1, 4, 1, 1, 4, 4, 1, 2, 1, 1, 4, 3, 4, 5, 1, 6, 2, 2, 1, 3, 1, 7, 4, 3, 3, 0, 4, 9, 5, 5, 1, 0, 6, 4, 2, 8, 2, 8, 1, 0, 3, 1, 1, 6, 7, 8, 4, 8, 3, 7, 3, 2, 0, 4, 4, 2, 9, 0, 5, 9, 5, 6, 1, 9, 0, 8, 6, 0, 4, 7, 2, 8, 8, 5, 2, 6, 8, 9, 1, 6, 0, 7, 3, 1, 1, 8, 1, 7, 6

Offset

1,3

Comments

Self-descriptive sequence: even terms are the sequence itself, odd terms are the digits of the decimal expansion of sqrt(2).

Links

Paolo Xausa, Table of n, a(n) for n = 1..10000

Clark Kimberling, Fractal sequences.

Formula

a(2n)=a(n); a(2n+1)=digits of sqrt(2).

a(n) = A002193(A003602(n)). - Paolo Xausa, Sep 12 2025

Mathematica

With[{nmax = 100}, RealDigits[Sqrt[2], 10, Ceiling[nmax/2]][[1, Table[(BitShiftRight[n, IntegerExponent[n, 2]] + 1)/2, {n, nmax}]]]] (* Paolo Xausa, Sep 12 2025 *)

Crossrefs

Cf. A002193 (sqrt(2)), A003602.

Cf. A110766 (of Pi), A110779 (of e), A382130 (of phi).

Sequence in context: A326039 A183374 A176263 * A151904 A356296 A222360

Adjacent sequences: A110809 A110810 A110811 * A110813 A110814 A110815

Keyword

easy,nonn,base

Author

Alexandre Wajnberg, Sep 15 2005

Extensions

More terms from Paolo Xausa, Sep 12 2025

Status

approved