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Decimal expansion of the seventh smallest known Salem number.
5

%I #4 Jul 08 2018 21:30:21

%S 1,2,3,0,3,9,1,4,3,4,4,0,7,2,2,4,7,0,2,7,9,0,1,7,7,9,3,8,9,7,5,2,7,9,

%T 0,1,7,5,6,6,5,7,4,4,8,9,6,6,1,7,5,6,2,4,1,4,0,1,9,1,4,2,3,6,1,7,2,8,

%U 1,3,4,4,7,8,5,3,5,4,5,4,1,6,7,3,5,9,8,4,6,5,1,6,6,2,4,0,8,5,2,8,5,6

%N Decimal expansion of the seventh smallest known Salem number.

%H M. J. Mossinghoff, <a href="http://www.cecm.sfu.ca/~mjm/Lehmer/lists/SalemList.html">Small Salem Numbers</a>

%H Eric Weisstein's MathWorld, <a href="http://mathworld.wolfram.com/SalemConstants.html">Salem Constants.</a>

%H Wikipedia, <a href="http://en.wikipedia.org/wiki/Salem_number">Salem number</a>

%F p = 1 - x^3 - x^5 - x^7 + x^10.

%e 1.2303914344072247027901779389752790175665744896617562414019142361728...

%t c1 = {1, 0, 0, -1, 0, -1};

%t c2 = Join[c1, Reverse[Most[c1]]];

%t p = (x^Range[0, Length[c2] - 1]).c2;

%t sigma7 = Root[p, x, 2];

%t RealDigits[sigma7, 10, 102][[1]]

%Y Cf. A073011 (sigma1), A219300 (sigma2), A306078 (sigma3 ), A306079 (sigma4), A316605 (sigma5), A316606 (sigma6), A316608 (sigma8), A316609 (sigma9), A316610 (sigma10).

%K nonn,cons

%O 1,2

%A _Jean-François Alcover_, Jul 08 2018