A306078 - OEIS

%I #5 Jun 19 2018 22:15:54

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

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

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

%N Decimal expansion of the third 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>

%e 1.200026523987391518902962100414601567240618151999851067924399839886...

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

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

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

%t sigma3 = Root[p, x, 2];

%t RealDigits[sigma3, 10, 100][[1]]

%Y Cf. A073011 (sigma1), A219300 (sigma2), A306079 (sigma4).

%K nonn,cons

%O 1,2

%A _Jean-François Alcover_, Jun 19 2018