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A260432
Permutation of natural numbers: a(1) = 1, a(2n) = A257804(a(n)), a(2n+1) = A257803(1+a(n)), where A257804 and A257803 give the positions of even and odd terms in A233271, the infinite trunk of inverted binary beanstalk.
4
1, 2, 4, 3, 7, 6, 12, 5, 9, 11, 21, 10, 18, 19, 30, 8, 17, 14, 24, 16, 27, 36, 54, 15, 25, 31, 49, 32, 52, 48, 74, 13, 23, 29, 42, 22, 35, 40, 60, 28, 41, 45, 68, 61, 83, 92, 132, 26, 38, 43, 64, 50, 75, 86, 119, 51, 76, 89, 128, 85, 118, 125, 172, 20, 34, 39, 57, 47, 73, 71, 106, 37, 55, 59, 82, 67, 96, 101, 140, 46, 70, 69
OFFSET
1,2
COMMENTS
This sequence can be represented as a binary tree. Each left hand child is produced as A257804(n), and each right hand child as A257803(1+n), when the parent contains n:
|
...................1...................
2 4
3......../ \........7 6......../ \........12
/ \ / \ / \ / \
/ \ / \ / \ / \
/ \ / \ / \ / \
5 9 11 21 10 18 19 30
8 17 14 24 16 27 36 54 15 25 31 49 32 52 48 74
etc.
FORMULA
a(1) = 1, a(2n) = A257804(a(n)), a(2n+1) = A257803(1+a(n)).
As a composition of other permutations:
a(n) = A260434(A054429(n)).
a(n) = A260430(A260434(n)).
PROG
(Scheme, with memoizing macro definec)
(definec (A260432 n) (cond ((<= n 1) n) ((even? n) (A257804 (A260432 (/ n 2)))) (else (A257803 (+ 1 (A260432 (/ (- n 1) 2)))))))
CROSSREFS
Inverse: A260431.
Related permutations: A260434, A260430, A054429.
Cf. also A233271, A257806.
Sequence in context: A266413 A245614 A246165 * A021808 A365215 A225252
KEYWORD
nonn,tabf
AUTHOR
Antti Karttunen, Jul 27 2015
STATUS
approved