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 A061855 Symmetric totally balanced binary sequences: those terms of A014486 which are equal to their reversed complement. 6
 0, 2, 10, 12, 42, 52, 56, 170, 178, 204, 212, 232, 240, 682, 722, 738, 812, 852, 868, 920, 936, 976, 992, 2730, 2762, 2866, 2898, 2978, 3010, 3244, 3276, 3380, 3412, 3492, 3524, 3640, 3672, 3752, 3784, 3888, 3920, 4000, 4032, 10922, 11082, 11146 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 COMMENTS These encode symmetric (palindromic) structures in many of the Catalan families, e.g. mountain ranges, parenthesizations, unlabeled rooted plane trees. LINKS A. Karttunen, Some notes on Catalan's Triangle FORMULA a(0) = 0 and the rest with the Maple function map(op, [seq(PalTotBalBinSequences(j), j=1..10)]); EXAMPLE E.g. the 45th term 11146 is 10101110001010 in binary and can be interpreted as a parenthesization: ( )( )((( )))( )( ) MAPLE map(op, [seq(PalTotBalBinSequences(j), j=1..10)]); PalTotBalBinSequences := n -> map(ReflectBinSeq, NonDivingLatticeSequences(n), n); CROSSREFS Obtained by "reflecting" the terms of A061854. Cf. also A035928 (ReflectBinSeq), A061856, A069766. Sequence in context: A075165 A209641 A209642 * A144145 A075170 A039571 Adjacent sequences:  A061852 A061853 A061854 * A061856 A061857 A061858 KEYWORD nonn AUTHOR Antti Karttunen, May 11 2001 STATUS approved

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Last modified August 8 05:50 EDT 2020. Contains 336290 sequences. (Running on oeis4.)