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%I #18 Aug 30 2021 21:40:52
%S 1,10,11,101,10111,101101,11101,11101101,1110111,10110111,
%T 1011011110111,10110111101101,1110111101101,111011110110111101101,
%U 11101111011011110111,101101111011011110111,1011011110110111101111011011110111,10110111101101111011110110111101101,1110111101101111011110110111101101
%N Lexicographically earliest sequence of distinct terms > 0 such that the concatenation of three successive terms form a palindrome in base 10.
%C This sequence shows only 0's and 1's. The lexicographically earliest sequence of distinct terms > 0 such that the concatenation of two successive terms form a palindrome in base 10 is A000042.
%e a(1) = 1, a(2) = 10, a(3) = 11 form the palindrome 11011 when concatenated;
%e a(2) = 10, a(3) = 11, a(4) = 101 form the palindrome 1011101 when concatenated;
%e a(3) = 11, a(4) = 101, a(5) = 10111 form the palindrome 1110110111 when concatenated;
%e a(4) = 101, a(5) = 10111, a(6) = 101101 form the palindrome 10110111101101 when concatenated; etc.
%Y Cf. A000042.
%K base,nonn
%O 1,2
%A _Eric Angelini_ and _Carole Dubois_, Aug 30 2021