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A277813
a(n) = A115384(A277812(n)) = index of the row where n is located in array A277880.
6
1, 2, 1, 3, 2, 1, 4, 5, 3, 2, 6, 1, 7, 8, 4, 9, 5, 3, 10, 2, 11, 12, 6, 1, 13, 14, 7, 15, 8, 4, 16, 17, 9, 5, 18, 3, 19, 20, 10, 2, 21, 22, 11, 23, 12, 6, 24, 1, 25, 26, 13, 27, 14, 7, 28, 29, 15, 8, 30, 4, 31, 32, 16, 33, 17, 9, 34, 5, 35, 36, 18, 3, 37, 38, 19, 39, 20, 10, 40, 2, 41, 42, 21, 43, 22, 11, 44, 45, 23, 12, 46, 6, 47, 48, 24, 1, 49, 50
OFFSET
1,2
COMMENTS
a(n) = index of the first odious number which is encountered when we start from k = n and iterate the map k -> A003188(A006068(k)/2).
Ordinal transform of A277822.
This works as a left inverse of A000069 like also does A115384.
FORMULA
a(n) = A115384(A277812(n)).
Other identities. For all n >= 1:
a(A000069(n)) = n.
a(n) = a(floor(n/2)) when A010060(n) = 0.
PROG
(Scheme) (define (A277813 n) (A115384 (A277812 n)))
CROSSREFS
Cf. A003945 (the positions of 1's in this sequence).
Sequence in context: A181971 A104741 A167237 * A200154 A208825 A344391
KEYWORD
nonn,base
AUTHOR
Antti Karttunen, Nov 03 2016
STATUS
approved