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%I #12 Jun 29 2014 03:02:21
%S 1,1,1,11,11,101,11,111,111,1001,101,101,11,101,111,1111,1111,10001,
%T 1001,1001,101,10101,1001,111,111,1001,101,11011,111,111,1111,11111,
%U 11111,100001,10001,10001,11011,1001,1001,1001,101,1001,10101,10101,1001,101101
%N Longest palindromic factor of (n base 2); in case of tie choose largest; if it begins with 0 complement it.
%C The "if it begins with 0 complement it" clause is required because nonzero terms in the OEIS may not begin with 0.
%H Lars Blomberg, <a href="/A215256/b215256.txt">Table of n, a(n) for n = 0..9999</a>
%e n=10 = 1010, longest palindromic factor is 101.
%e n=12 = 1100, there are two palindromic factors of length 2, namely 11 and 00, and we choose the larger, 11.
%e n=24 = 11000, longest palindromic factor is 000, complementing gives 111.
%Y Cf. A050430, A215467.
%K nonn,base
%O 0,4
%A _N. J. A. Sloane_, Aug 15 2012
%E More terms from _Lars Blomberg_, Jun 29 2014