A038775 a(n) is the number of cycles of the permutation that converts forest(n) of depth-first planar planted binary trees into breadth-first representation.

1, 2, 3, 6, 10, 12, 17, 26, 34, 50, 56, 68, 82, 94, 113

Offset

1,2

Comments

The first a(n) terms of A038774 add up to Catalan(n) = A000108(n).

Links

Table of n, a(n) for n=1..15.

Sean A. Irvine, Java program (github)

Example

a(5)=10 since there are 10 cycles in this permutation of forest(5), with lengths 1, 1, 3, 4, 3, 2, 16, 8, 2, 2 summing up to 42=Catalan(5).

Crossrefs

Cf. A000108, A038774.

Similarly generated sequences: A001683, A002995, A003239, A057507, A057513.

Sequence in context: A104074 A140785 A355177 * A065029 A239212 A280558

Adjacent sequences: A038772 A038773 A038774 * A038776 A038777 A038778

Keyword

nonn,more

Author

Wouter Meeussen, May 04 2000

Extensions

a(13)-a(15) from Sean A. Irvine, May 22 2022

Status

approved