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A046095 Decimal expansion of Calabi's constant. 1
1, 5, 5, 1, 3, 8, 7, 5, 2, 4, 5, 4, 8, 3, 2, 0, 3, 9, 2, 2, 6, 1, 9, 5, 2, 5, 1, 0, 2, 6, 4, 6, 2, 3, 8, 1, 5, 1, 6, 3, 5, 9, 1, 7, 0, 3, 8, 0, 3, 8, 8, 7, 1, 9, 9, 5, 2, 8, 0, 0, 7, 1, 2, 0, 1, 1, 7, 9, 2, 6, 7, 4, 2, 5, 5, 4, 2, 5, 6, 9, 5, 7, 2, 9, 5, 7, 6, 0, 4, 5, 3, 6, 1, 2, 0, 2, 5, 4, 3, 6, 2, 9 (list; constant; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

An algebraic number of degree 3. - Charles R Greathouse IV, Oct 31 2014

REFERENCES

John H. Conway & Richard K. Guy, The Book of Numbers. Copernicus (Springer-Verlag) (1996), p. 206

LINKS

Table of n, a(n) for n=1..102.

E. Calabi, Outline of Proof Regarding Squares Wedged in Triangle

Eric Weisstein's World of Mathematics, Calabi's Triangle.

FORMULA

Equals (28*c+2)/sqrt(196*c^2+28*c+145) where c = cos(arctan(12*sqrt(237)/289)/3). - Robert FERREOL, Jun 22 2019

MATHEMATICA

RealDigits[ x /. FindRoot[ 2x^3-2x^2-3x+2==0, {x, 1.5}, WorkingPrecision->200 ], 10 ][ [ 1 ] ]

RealDigits[ Root[ 2x^3-2x^2-3x+2, x, 3], 10, 102][[1]] (* Jean-Fran├žois Alcover, Jun 18 2014 *)

PROG

(PARI) polrootsreal(2*x^3-2*x^2-3*x+2)[3] \\ Charles R Greathouse IV, Oct 31 2014

CROSSREFS

Cf. A046096.

Sequence in context: A145227 A236555 A282969 * A322545 A256737 A055183

Adjacent sequences:  A046092 A046093 A046094 * A046096 A046097 A046098

KEYWORD

nonn,cons

AUTHOR

Eric W. Weisstein

STATUS

approved

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Last modified October 19 21:28 EDT 2019. Contains 328244 sequences. (Running on oeis4.)