A289000 Length of n-th iterate of the mapping 00->0010, 01->001, 10->001, starting with 00.

2, 4, 7, 12, 20, 34, 58, 99, 169, 288, 491, 837, 1428, 2437, 4159, 7099, 12118, 20686, 35312, 60280, 102903, 175665, 299877, 511920, 873900, 1491838, 2546724, 4347527, 7421690, 12669614, 21628381, 36921953, 63029713, 107598447, 183682035, 313564844, 535288668

Offset

0,1

Links

Table of n, a(n) for n=0..36.

Mathematica

z = 20; (* number of iterates *)
s = {0, 0}; w[0] = StringJoin[Map[ToString, s]];
w[n_] := StringReplace[w[n - 1], {"00" -> "0010", "01" -> "001", "10" -> "001"}]
TableForm[Table[w[n], {n, 0, 10}]]
Table[StringLength[w[n]], {n, 0, 20}] (* A289000 *)

Crossrefs

Cf. A288991, A288997.

Sequence in context: A094925 A289168 A340217 * A289028 A186537 A079970

Adjacent sequences: A288997 A288998 A288999 * A289001 A289002 A289003

Keyword

nonn,easy

Author

Clark Kimberling, Jun 25 2017

Extensions

a(27)-a(36) from Lars Blomberg, Jul 05 2017

Status

approved