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 A346821 Lexicographically earliest sequence of distinct terms > 0 such that the concatenation of three successive terms form a palindrome in base 10. 0
 1, 10, 11, 101, 10111, 101101, 11101, 11101101, 1110111, 10110111, 1011011110111, 10110111101101, 1110111101101, 111011110110111101101, 11101111011011110111, 101101111011011110111, 1011011110110111101111011011110111, 10110111101101111011110110111101101, 1110111101101111011110110111101101 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS 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. LINKS EXAMPLE a(1) = 1, a(2) = 10, a(3) = 11 form the palindrome 11011 when concatenated; a(2) = 10, a(3) = 11, a(4) = 101 form the palindrome 1011101 when concatenated; a(3) = 11, a(4) = 101, a(5) = 10111 form the palindrome 1110110111 when concatenated; a(4) = 101, a(5) = 10111, a(6) = 101101 form the palindrome 10110111101101 when concatenated; etc. CROSSREFS Cf. A000042. Sequence in context: A305379 A004685 A171000 * A222365 A041216 A094026 Adjacent sequences:  A346818 A346819 A346820 * A346822 A346823 A346824 KEYWORD base,nonn AUTHOR Eric Angelini and Carole Dubois, Aug 30 2021 STATUS approved

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Last modified December 7 20:39 EST 2021. Contains 349589 sequences. (Running on oeis4.)