cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

Showing 1-3 of 3 results.

A179752 Maximum depth of parenthesizations encoded by A014486, or correspondingly, maximum height for the equivalent general trees.

Original entry on oeis.org

0, 1, 1, 2, 1, 2, 2, 2, 3, 1, 2, 2, 2, 3, 2, 2, 2, 2, 3, 3, 3, 3, 4, 1, 2, 2, 2, 3, 2, 2, 2, 2, 3, 3, 3, 3, 4, 2, 2, 2, 2, 3, 2, 2, 2, 2, 3, 3, 3, 3, 4, 3, 3, 3, 3, 3, 3, 3, 3, 4, 4, 4, 4, 4, 5, 1, 2, 2, 2, 3, 2, 2, 2, 2, 3, 3, 3, 3, 4, 2, 2, 2, 2, 3, 2, 2, 2, 2, 3, 3, 3, 3, 4, 3, 3, 3, 3, 3, 3, 3, 3, 4
Offset: 0

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Author

Antti Karttunen, Aug 03 2010

Keywords

Comments

Each integer n appears first at position given by A014138.

Examples

			The terms A014486[1..8] encode the following rooted plane general trees:
.1.......2.......3.......4.......5.......6.......7.......8.
...........................................................
.........................................................o.
.........................................................|.
.................o.................o...o.......o...o.....o.
.................|.................|...|........\./......|.
.o.....o...o.....o.....o.o.o...o...o...o...o.....o.......o.
.|......\./......|......\|/.....\./.....\./......|.......|.
.*.......*.......*.......*.......*.......*.......*.......*.
and the corresponding parenthesizations:
.().....()()....(())...()()()..()(())..(())()..(()())..((()))
thus a(1)=1, a(2)=1, a(3)=2, a(4)=1, a(5)=2, a(6)=2, a(7)=2, a(8)=3.
		

Crossrefs

Programs

  • Mathematica
    blist[m_] := Select[Map[Accumulate, Permutations[PadLeft[Table[1, m], 2*m, -1]]], Min[#] >= 0 &]; Join[{{0}}, Array[Map[Max, blist[#]] &, 6]] (* Paolo Xausa, Mar 04 2024 *)

A126304 a(n) = number of nodes with nonzero even distance to the root in the n-th plane general tree encoded by A014486(n).

Original entry on oeis.org

0, 0, 0, 1, 0, 1, 1, 2, 1, 0, 1, 1, 2, 1, 1, 2, 2, 3, 2, 1, 2, 1, 2, 0, 1, 1, 2, 1, 1, 2, 2, 3, 2, 1, 2, 1, 2, 1, 2, 2, 3, 2, 2, 3, 3, 4, 3, 2, 3, 2, 3, 1, 2, 2, 3, 2, 1, 2, 1, 2, 2, 3, 2, 3, 2, 0, 1, 1, 2, 1, 1, 2, 2, 3, 2, 1, 2, 1, 2, 1, 2, 2, 3, 2, 2, 3, 3, 4, 3, 2, 3, 2, 3, 1, 2, 2, 3, 2, 1, 2, 1, 2
Offset: 0

Views

Author

Antti Karttunen, Jan 02 2007

Keywords

Examples

			A014486(27) = 696 (1010111000 in binary), encodes the following general plane tree, where the root is marked with * and nodes with even or odd distance to root with 'e's and 'o's, respectively.
.......o
.......|
.......e
.......|
...o.o.o
....\|/.
.....*..
there is one node marked with 'e', thus a(27)=1.
		

Crossrefs

a(n) = A126305(n)-1. Cf. A126303. Scheme-function A014486->parenthesization given in A014486.

Programs

A126305 a(n) = number of nodes with even distance to the root in the n-th plane general tree encoded by A014486(n). The root node itself is also included.

Original entry on oeis.org

1, 1, 1, 2, 1, 2, 2, 3, 2, 1, 2, 2, 3, 2, 2, 3, 3, 4, 3, 2, 3, 2, 3, 1, 2, 2, 3, 2, 2, 3, 3, 4, 3, 2, 3, 2, 3, 2, 3, 3, 4, 3, 3, 4, 4, 5, 4, 3, 4, 3, 4, 2, 3, 3, 4, 3, 2, 3, 2, 3, 3, 4, 3, 4, 3, 1, 2, 2, 3, 2, 2, 3, 3, 4, 3, 2, 3, 2, 3, 2, 3, 3, 4, 3, 3, 4, 4, 5, 4, 3, 4, 3, 4, 2, 3, 3, 4, 3, 2, 3, 2, 3
Offset: 0

Views

Author

Antti Karttunen, Jan 02 2007

Keywords

Crossrefs

a(n) = A126304(n)+1 = A072643(n)-A126303(n). a(n) = A057514(A125982(n)) for all n >=1.
Showing 1-3 of 3 results.