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A293506
Decimal expansion of real root of x^5 - x^4 - x^2 - 1.
15
1, 5, 7, 0, 1, 4, 7, 3, 1, 2, 1, 9, 6, 0, 5, 4, 3, 6, 2, 9, 1, 0, 6, 6, 5, 4, 3, 5, 1, 3, 7, 1, 2, 6, 5, 5, 3, 8, 7, 3, 1, 3, 1, 6, 0, 7, 4, 2, 4, 5, 2, 7, 4, 3, 6, 9, 3, 1, 6, 5, 4, 8, 7, 7, 8, 9, 7, 3, 3, 0, 6, 6, 1, 5, 4, 4, 1, 6, 2, 3, 2, 0, 2, 2, 2, 7, 6
OFFSET
1,2
COMMENTS
This root is also the ninth smallest of the Pisot numbers.
The ratio of successive terms of A122115 converges to this number.
LINKS
Hans Walser, Funktionenfolge [in German]
Eric Weisstein's World of Mathematics, Pisot Number.
EXAMPLE
1.570147312196054362910665...
MATHEMATICA
First@ RealDigits[Root[#^5 - #^4 - #^2 - 1 &, 1], 10, 87] (* Michael De Vlieger, Oct 23 2017 *)
PROG
(PARI) solve(x=1, 2, x^5 - x^4 - x^2 - 1) \\ Michel Marcus, Oct 11 2017
(PARI) default(realprecision, 20080); x=solve(x=1, 2, x^5 - x^4 - x^2 - 1); for (n=1, 20000, d=floor(x); x=(x-d)*10; write("b293506.txt", n, " ", d));
CROSSREFS
KEYWORD
cons,nonn
AUTHOR
Iain Fox, Oct 10 2017
EXTENSIONS
More terms from Andrey Zabolotskiy, Oct 12 2017
STATUS
approved