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.

A270202 Permutation of natural numbers: a(1) = 1, a(2n) = A270189(1+a(n)), a(2n+1) = A270190(a(n)).

Original entry on oeis.org

1, 2, 9, 3, 11, 12, 36, 4, 15, 14, 39, 17, 40, 52, 108, 5, 16, 22, 51, 20, 47, 59, 114, 25, 55, 60, 118, 77, 167, 156, 312, 6, 18, 24, 54, 30, 73, 75, 165, 28, 67, 68, 139, 85, 185, 166, 339, 34, 84, 80, 174, 87, 187, 173, 347, 117, 227, 254, 496, 236, 461, 475, 852, 7, 21, 26, 56, 33, 76, 79, 170, 43, 99, 112, 216, 115, 219, 251, 490, 41
Offset: 1

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Author

Antti Karttunen, Mar 16 2016

Keywords

Comments

This sequence can be represented as a binary tree. Each left hand child is produced as A270189(1+n), and each right hand child as A270190(n), when the parent node contains n:
1
................../ \..................
2 9
3......../ \........11 12......../ \........36
/ \ / \ / \ / \
/ \ / \ / \ / \
/ \ / \ / \ / \
4 15 14 39 17 40 52 108
5 16 22 51 20 47 59 114 25 55 60 118 77 167 156 312
etc.

Crossrefs

Inverse: A270201.
Similar permutation: A270194.

Formula

a(1) = 1, a(2n) = A270189(1+a(n)), a(2n+1) = A270190(a(n)).