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A268818
Permutation of nonnegative integers: a(n) = A268718(A268718(n)).
3
0, 1, 6, 4, 3, 10, 2, 7, 15, 5, 14, 11, 8, 13, 18, 16, 23, 29, 22, 19, 32, 21, 9, 24, 12, 25, 30, 28, 27, 34, 26, 31, 39, 45, 38, 35, 48, 37, 57, 40, 60, 41, 46, 44, 43, 17, 42, 47, 20, 49, 54, 52, 51, 58, 50, 55, 63, 53, 62, 59, 56, 61, 66, 64, 71, 77, 70, 67, 80, 69, 89, 72, 92, 73, 78, 76, 75, 113, 74, 79, 116, 81
OFFSET
0,3
FORMULA
a(n) = A268718(A268718(n)).
PROG
(Scheme) (define (A268818 n) (A268718 (A268718 n)))
(Python)
def a003188(n): return n^(n>>1)
def a006068(n):
s=1
while True:
ns=n>>s
if ns==0: break
n=n^ns
s<<=1
return n
def a278618(n): return 0 if n==0 else 1 + a003188(a006068(n) - 1)
def a(n): return a278618(a278618(n)) # Indranil Ghosh, Jun 07 2017
CROSSREFS
Inverse: A268817.
Cf. A268718.
Cf. also A268822.
Sequence in context: A268817 A372365 A020794 * A112148 A007258 A045488
KEYWORD
nonn
AUTHOR
Antti Karttunen, Feb 14 2016
STATUS
approved