A167289 Signature sequence of the smallest Salem number of degree 18 (A219300).

1, 2, 1, 3, 2, 1, 4, 3, 2, 1, 5, 4, 3, 2, 1, 6, 5, 4, 3, 2, 1, 7, 6, 5, 4, 3, 2, 8, 1, 7, 6, 5, 4, 3, 9, 2, 8, 1, 7, 6, 5, 4, 10, 3, 9, 2, 8, 1, 7, 6, 5, 11, 4, 10, 3, 9, 2, 8, 1, 7, 6, 12, 5, 11, 4, 10, 3, 9, 2, 8, 1, 7, 13, 6, 12, 5, 11, 4, 10, 3, 9, 2, 8, 14, 1, 7, 13, 6, 12, 5, 11, 4, 10, 3, 9, 15

Offset

1,2

Links

G. C. Greubel, Table of n, a(n) for n = 1..5000

Michael Mossinghoff, Lehmer's Problem Website.

Michael Mossinghoff, Small Salem Numbers.

Eric Weisstein's World of Mathematics, Signature Sequence.

Mathematica

a = {1, -1, 1, -1, 0, 0, -1, 1, -1};
b = Join[a, {1}, Reverse[a]];
p[x_] = Sum[b[[n]]*x^(n - 1), {n, 1, Length[b]}];
m = Root[p[x], 2];
Take[Transpose[Sort[Flatten[Table[{i + j*m, i}, {i, 25}, {j, 17}], 1], #1[[1]] < #2[[1]] &]][[2]], 95]

Crossrefs

Cf. A073011, A147851, A219300.

Sequence in context: A200370 A200443 A167288 * A200329 A023122 A200272

Adjacent sequences: A167286 A167287 A167288 * A167290 A167291 A167292

Keyword

nonn,less

Author

Roger L. Bagula, Nov 01 2009

Status

approved