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A273666
Permutation of nonnegative integers: a(0) = 0; after which, a(2n) = A153880(a(n)), a(2n+1) = A273670(a(n)).
6
0, 1, 2, 3, 6, 4, 8, 5, 24, 10, 12, 7, 30, 13, 14, 9, 120, 34, 36, 16, 48, 18, 26, 11, 144, 42, 50, 19, 54, 20, 32, 15, 720, 154, 156, 46, 168, 49, 60, 22, 240, 66, 72, 25, 126, 37, 38, 17, 840, 186, 192, 58, 246, 68, 74, 27, 264, 73, 78, 28, 150, 44, 56, 21, 5040, 874, 876, 199, 888, 202, 204, 64, 960, 216, 242, 67, 288, 82, 84, 31
OFFSET
0,3
COMMENTS
This sequence can be represented as a binary tree. Each left hand child is produced as A153880(n), and each right hand child as A273670(n), when their parent contains n >= 1:
0
|
...................1...................
2 3
6......../ \........4 8......../ \........5
/ \ / \ / \ / \
/ \ / \ / \ / \
/ \ / \ / \ / \
24 10 12 7 30 13 14 9
120 34 36 16 48 18 26 11 144 42 50 19 54 20 32 15
etc.
FORMULA
a(0) = 0; after which, a(2n) = A153880(a(n)), a(2n+1) = A273670(a(n)).
PROG
(Scheme, with memoization-macro definec)
(definec (A273666 n) (cond ((zero? n) n) ((even? n) (A153880 (A273666 (/ n 2)))) (else (A273670 (A273666 (/ (- n 1) 2))))))
CROSSREFS
Inverse: A273665.
Related or similar permutations: A255566, A273668.
Sequence in context: A257987 A372132 A132169 * A302023 A112975 A257218
KEYWORD
nonn,base,tabf
AUTHOR
Antti Karttunen, May 30 2016
STATUS
approved