A330717 - OEIS

A330717

a(n) is the greatest binary palindrome of the form floor(n/2^k) with k >= 0.

0, 1, 1, 3, 1, 5, 3, 7, 1, 9, 5, 5, 3, 3, 7, 15, 1, 17, 9, 9, 5, 21, 5, 5, 3, 3, 3, 27, 7, 7, 15, 31, 1, 33, 17, 17, 9, 9, 9, 9, 5, 5, 21, 21, 5, 45, 5, 5, 3, 3, 3, 51, 3, 3, 27, 27, 7, 7, 7, 7, 15, 15, 31, 63, 1, 65, 33, 33, 17, 17, 17, 17, 9, 73, 9, 9, 9, 9

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OFFSET

0,4

COMMENTS

In other words, a(n) is the greatest binary palindromic prefix of n.

LINKS

Rémy Sigrist, Table of n, a(n) for n = 0..8192

Index entries for sequences related to binary expansion of n

FORMULA

A070939(a(n)) = A215467(n).

a(n) = 1 iff n is a power of 2.

a(n) <= n with equality iff n is a binary palindrome (A006995).