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A215256
Longest palindromic factor of (n base 2); in case of tie choose largest; if it begins with 0 complement it.
2
1, 1, 1, 11, 11, 101, 11, 111, 111, 1001, 101, 101, 11, 101, 111, 1111, 1111, 10001, 1001, 1001, 101, 10101, 1001, 111, 111, 1001, 101, 11011, 111, 111, 1111, 11111, 11111, 100001, 10001, 10001, 11011, 1001, 1001, 1001, 101, 1001, 10101, 10101, 1001, 101101
OFFSET
0,4
COMMENTS
The "if it begins with 0 complement it" clause is required because nonzero terms in the OEIS may not begin with 0.
LINKS
EXAMPLE
n=10 = 1010, longest palindromic factor is 101.
n=12 = 1100, there are two palindromic factors of length 2, namely 11 and 00, and we choose the larger, 11.
n=24 = 11000, longest palindromic factor is 000, complementing gives 111.
CROSSREFS
Sequence in context: A241870 A243127 A088761 * A265526 A265559 A265543
KEYWORD
nonn,base
AUTHOR
N. J. A. Sloane, Aug 15 2012
EXTENSIONS
More terms from Lars Blomberg, Jun 29 2014
STATUS
approved