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.

A075171 Nonnegative integers mapped to Dyck path encodings of the rooted plane trees obtained by recursing on the run lengths of the binary expansion of n.

Original entry on oeis.org

0, 10, 1010, 1100, 101100, 101010, 110010, 110100, 10110100, 10110010, 10101010, 10101100, 11001100, 11001010, 11010010, 111000, 10111000, 1011010010, 1011001010, 1011001100, 1010101100, 1010101010, 1010110010, 1010110100
Offset: 0

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Author

Antti Karttunen, Sep 13 2002

Keywords

Examples

			The rooted plane trees encoded here are:
.....................o........o.........o......o...o...
.....................|........|.........|.......\./....
.......o....o...o....o....o...o..o.o.o..o...o....o.....
.......|.....\./.....|.....\./....\|/....\./.....|.....
(AT)......(AT)......(AT)......(AT)......(AT)......(AT)......(AT)......(AT).....
0......1......2......3......4......5......6......7.....
Note that we recurse on the run length - 1, thus for 4 = 100 in binary, we construct a tree by joining trees 0 (= 1-1) and 1 (= 2-1) respectively from left to right. For 5 (101) we construct a tree by joining three copies of tree 0 (a single leaf) with a new root node. For 6 (110) we join trees 1 and 0 to get a mirror image of tree 4. For 7 (111) we just add a new root node below tree 2.
		

Crossrefs

Permutation of A063171. Same sequence shown in decimal: A075170. The digital length of each term / 2 (the number of o-nodes in the corresponding trees) is given by A075172. Cf. A075166, A007088.