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A270426
Permutation of natural numbers: a(1) = 1, a(2n) = 2*a(n), a(2n+1) = A265341(a(n)).
2
1, 2, 3, 4, 7, 6, 5, 8, 9, 14, 19, 12, 13, 10, 21, 16, 25, 18, 11, 28, 63, 38, 23, 24, 17, 26, 27, 20, 15, 42, 37, 32, 57, 50, 73, 36, 31, 22, 39, 56, 33, 126, 91, 76, 117, 46, 61, 48, 43, 34, 75, 52, 79, 54, 29, 40, 67, 30, 49, 84, 157, 74, 45, 64, 147, 114, 41, 100, 183, 146, 77, 72, 35, 62, 51, 44, 55, 78, 53, 112, 193, 66
OFFSET
1,2
COMMENTS
This sequence can be represented as a binary tree. Each left hand child will contain 2n, and each right hand child will contain A265341(n), when the parent node contains n:
1
................../ \..................
2 3
4......../ \........7 6......../ \........5
/ \ / \ / \ / \
/ \ / \ / \ / \
/ \ / \ / \ / \
8 9 14 19 12 13 10 21
16 25 18 11 28 63 38 23 24 17 26 27 20 15 42 37
etc.
FORMULA
a(1) = 1, a(2n) = 2*a(n), a(2n+1) = A265341(a(n)).
PROG
(Scheme, with memoization-macro definec)
(definec (A270426 n) (cond ((= 1 n) n) ((even? n) (* 2 (A270426 (/ n 2)))) (else (A265341 (A270426 (/ (- n 1) 2))))))
CROSSREFS
Inverse: A270425.
Cf. A265341.
Sequence in context: A072026 A332213 A235199 * A270425 A332212 A085161
KEYWORD
nonn,base,less,tabf
AUTHOR
Antti Karttunen, Mar 17 2016
STATUS
approved