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A293557 Decimal expansion of real root of x^7 - x^6 - x^5 + x^2 - 1.

%I A293557 #30 Feb 16 2025 08:36:01
%S A293557 1,5,4,5,2,1,5,6,4,9,7,3,2,7,5,5,2,4,3,2,5,2,5,5,0,6,2,4,1,0,5,1,1,6,
%T A293557 1,1,9,6,9,1,4,7,0,0,5,5,3,6,4,2,3,3,1,2,3,5,6,0,6,1,0,7,2,5,4,9,8,2,
%U A293557 1,1,5,8,8,1,6,6,5,3,3,1,2,0,5,0,4,3,1
%N A293557 Decimal expansion of real root of x^7 - x^6 - x^5 + x^2 - 1.
%C A293557 This root is also the seventh smallest of the Pisot numbers.
%H A293557 Iain Fox, <a href="/A293557/b293557.txt">Table of n, a(n) for n = 1..20000</a>
%H A293557 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/PisotNumber.html">Pisot Number</a>.
%H A293557 Wikipedia, <a href="https://en.wikipedia.org/wiki/Pisot%E2%80%93Vijayaraghavan_number">Pisot-Vijayaraghavan number</a>
%H A293557 <a href="/index/Al#algebraic_07">Index entries for algebraic numbers, degree 7</a>.
%e A293557 1.545215649732755243252550...
%t A293557 First[RealDigits[Root[#^7 - #^6 - #^5 + #^2 - 1 &, 1], 10, 100]] (* _Paolo Xausa_, Jun 25 2024 *)
%o A293557 (PARI) solve(x=1, 2, x^7 - x^6 - x^5 + x^2 - 1) \\ _Michel Marcus_, Oct 13 2017
%o A293557 (PARI) { default(realprecision, 20080); x=solve(x=1, 2, x^7 - x^6 - x^5 + x^2 - 1); for (n=1, 20000, d=floor(x); x=(x-d)*10; write("b293557.txt", n, " ", d)); }
%Y A293557 Cf. A060006, A086106, A228777, A092526, A293508, A293509, A374002, A293506,  A374003.
%K A293557 cons,nonn
%O A293557 1,2
%A A293557 _Iain Fox_, Oct 11 2017