A347539 Matula-Goebel number of the n-th tree in Beyer and Hedetniemi's rooted tree iteration (A346913).

1, 2, 3, 4, 5, 7, 6, 8, 11, 17, 13, 10, 19, 14, 9, 12, 16, 31, 59, 41, 29, 22, 67, 43, 34, 23, 37, 26, 15, 20, 53, 38, 21, 28, 18, 24, 32, 127, 277, 179, 109, 79, 62, 331, 191, 139, 118, 83, 157, 101, 82, 47, 71, 58, 33, 44, 241, 163, 134, 73, 107, 86, 51, 68

Offset: 1

Author

Kevin Ryde, Sep 06 2021

Keywords

• nonn

Comments

This sequence is a permutation of the natural numbers, with inverse A347540.

Examples

			For n=33, row 33 of A346913 is levels sequence 1,2,3,3,2,3 which is the following tree,
  root      21          a(33) = 21 Matula-Goebel number
            |  \        (being prime(4)*prime(2) = 21)
  children  4    2
            |\   |
            1 1  1
		

Links

• Kevin Ryde, Table of n, a(n) for n = 1..7813 (trees <= 12 vertices)
• Index entries for sequences that are permutations of the natural numbers

Crossrefs

Cf. A346913, A347540 (inverse), A061773, A127301.