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A269357
Permutation of natural numbers: a(1) = 1, a(2n) = 2*a(n), a(2n+1) = A269380(A250469(2n+1)).
5
1, 2, 3, 4, 5, 6, 7, 8, 23, 10, 11, 12, 13, 14, 15, 16, 9, 46, 17, 20, 31, 22, 25, 24, 21, 26, 27, 28, 19, 30, 29, 32, 49, 18, 71, 92, 37, 34, 39, 40, 41, 62, 43, 44, 107, 50, 47, 48, 119, 42, 51, 52, 35, 54, 89, 56, 101, 38, 53, 60, 61, 58, 63, 64, 115, 98, 67, 36, 173, 142, 55, 184, 33, 74, 75, 68, 131, 78, 77, 80, 167
OFFSET
1,2
COMMENTS
This is a variant of A269355, from which it differs for the first time at n=18.
FORMULA
a(1) = 1, after which, for even n, a(n) = 2*a(n/2) and for odd n, a(n) = A269355(n) = A269380(A250469(n)).
Other identities. For all n >= 1:
A000035(a(n)) = A000035(n). [This permutation preserves the parity of n.]
PROG
(Scheme, with memoization-macro definec)
(definec (A269357 n) (cond ((<= n 1) n) ((even? n) (* 2 (A269357 (/ n 2)))) (else (A269380 (A250469 n)))))
CROSSREFS
KEYWORD
nonn
AUTHOR
Antti Karttunen, Mar 03 2016
STATUS
approved