A240972 Lexicographically earliest sequence such that (i) the binary plot of the sequence is symmetric with respect to the line y=x and (ii) the derived sequence (A000265(a(n))) contains only distinct terms.

1, 6, 10, 28, 72, 352, 240, 832, 672, 2432, 17408, 12800, 47104, 55296, 41984, 126976, 950272, 2162688, 2424832, 3211264, 18350080, 5111808, 90177536, 377487360, 55574528, 394264576, 247463936, 3422552064, 578813952, 14763950080

Offset

1,2

Comments

The first constraint means that writing the binary representation of each number vertically yields a symmetrical plot about the line y = x (see the binary plot).

The second constraint ensures that the sequence contains only distinct terms, and differs from A000079.

The keywords "nice" and "look" are based on the fact that the binary plot is very interesting. - N. J. A. Sloane, Aug 22 2014

Links

Paul Tek, Table of n, a(n) for n = 1..3313

Paul Tek, Binary plot of the first hundred terms

Paul Tek, Perl program for this sequence

Eric Weisstein's World of Mathematics, Binary Plot

Prog

(Perl) See Link section.

Crossrefs

Cf. A230598, A240992 (odd part).

Sequence in context: A129545 A097578 A300098 * A349846 A103767 A025129

Adjacent sequences: A240969 A240970 A240971 * A240973 A240974 A240975

Keyword

nonn,base,nice,look

Author

Paul Tek, Aug 05 2014

Status

approved