A350505 Irregular triangle read by rows: a(n) is the n-th term of a truncated Kolakoski tree.

1, 2, 7, 3, 4, 15, 24, 5, 6, 14, 10, 35, 122, 36, 37, 11, 61, 8, 9, 21, 22, 34, 23, 53, 54, 184, 185, 55, 56, 84, 126, 16, 17, 136, 311, 12, 13, 20, 48, 32, 33, 113, 51, 392, 78, 52, 79, 119, 405, 80, 81, 277, 278, 414, 621, 82, 83, 283, 125, 425, 191, 2166, 288

Offset

1,2

Comments

Construct a tree with these rules: The root node is labeled 1. Children of odd indices are labeled 2. Children of even indices are labeled 1. Nodes labeled 1 have one child. Nodes labeled 2 have two children. At this point, the values of the n-th row comprise the digits in A111081(n). Replace each node labeled 2 with the positive integers in breadth-first order. Remove all nonbranching nodes.

Links

Rémy Sigrist, Table of n, a(n) for n = 1..5000

Rémy Sigrist, Illustration of the construction

Rémy Sigrist, C++ program

Index entries for sequences that are permutations of the natural numbers

Example

Triangle begins:
  1;
  2, 7;
  3, 4, 15, 24;
  5, 6, 14, 10, 35, 122, 36, 37;
...

Prog

(C++) See Links section.

Crossrefs

Inverse is A350506.

Cf. A111081.

Sequence in context: A371707 A226626 A249778 * A326661 A326662 A345038

Adjacent sequences: A350502 A350503 A350504 * A350506 A350507 A350508

Keyword

nonn,look,tabf

Author

John-Vincent Saddic, Jan 02 2022

Status

approved