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A167289
Signature sequence of the smallest Salem number of degree 18 (A219300).
2
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
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
KEYWORD
nonn,less
AUTHOR
Roger L. Bagula, Nov 01 2009
STATUS
approved