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A253555
a(1) = 0, a(2n) = 1 + a(n), a(2n+1) = 1 + a(A250470(2n+1)); also binary width of terms of A252754 and A252756.
8
0, 1, 2, 2, 3, 3, 4, 3, 3, 4, 5, 4, 6, 5, 4, 4, 7, 4, 8, 5, 4, 6, 9, 5, 4, 7, 5, 6, 10, 5, 11, 5, 5, 8, 5, 5, 12, 9, 6, 6, 13, 5, 14, 7, 5, 10, 15, 6, 5, 5, 5, 8, 16, 6, 5, 7, 6, 11, 17, 6, 18, 12, 7, 6, 6, 6, 19, 9, 6, 6, 20, 6, 21, 13, 8, 10, 6, 7, 22, 7, 7, 14, 23, 6, 6, 15, 6, 8, 24, 6, 6, 11, 6, 16, 7, 7, 25, 6, 9, 6
OFFSET
1,3
COMMENTS
a(n) tells how many iterations of A253554 are needed before 1 is reached, i.e., the distance of n from 1 in binary trees like A252753 and A252755.
LINKS
FORMULA
a(1) = 0; for n > 1: a(n) = 1 + a(A253554(n)).
a(n) = A029837(1+A252754(n)) = A029837(1+A252756(n)).
a(n) = A253556(n) + A253557(n).
Other identities.
For all n >= 1:
a(A000079(n)) = n. [I.e., a(2^n) = n.]
a(A000040(n)) = n.
a(A001248(n)) = n+1.
For n >= 2, a(n) = A253558(n) + A253559(n).
PROG
(Scheme, three versions, first one using memoization macro definec)
(definec (A253555 n) (if (<= n 1) 0 (+ 1 (A253555 (A253554 n)))))
(define (A253555 n) (A029837 (+ 1 (A252754 n))))
(define (A253555 n) (A029837 (+ 1 (A252756 n))))
CROSSREFS
Differs from A252464 for the first time at n=21, where a(21) = 4, while A252463(21) = 5.
Sequence in context: A230697 A322163 A075167 * A252464 A324861 A324863
KEYWORD
nonn
AUTHOR
Antti Karttunen, Jan 12 2015
STATUS
approved