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Number of binary palindromes of length 2n+1 having no (7/3)+ powers.
2

%I #8 Dec 16 2016 06:33:26

%S 2,2,2,2,2,2,4,6,6,4,6,10,10,12,16,20,20,26,34,46,50,60,68,88,112,134,

%T 166,196,240,288,348,428,524,618,758,930,1142,1384,1680,2066,2516,

%U 3056,3746,4562,5568,6780,8254,10098,12310,15042,18346,22360,27332,33318,40632,49702,60594,73986

%N Number of binary palindromes of length 2n+1 having no (7/3)+ powers.

%C A (7/3)+ power is a word of the form xxx', where x' is a prefix of x and |x'| > |x|/3. Every odd length (2n+1) is guaranteed to have at least one such palindrome.

%e For n = 6 the 4 palindromes avoiding (7/3)+ powers are {0011001001100, 0100110110010, 1011001001101, 1100110110011}.

%K nonn

%O 0,1

%A _Jeffrey Shallit_, Dec 15 2016