A298751 Decimal expansion of (1/2)(1 + sqrt(-3 + 4*sqrt(5))).

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

Offset

1,2

Links

Clark Kimberling, Table of n, a(n) for n = 1..10000

Index entries for algebraic numbers, degree 4.

Formula

Minimal polynomial x^4-2*x^3+3*x^2-2*x-4. - R. J. Mathar, Jun 03 2026

Example

constant = 1.7190438784144685973... = positive zero of x^2 - x + 1- sqrt(5).

Mathematica

r = (1/2)*(1 + Sqrt[-3 + 4 Sqrt[5]])
RealDigits[N[r, 100], 10][[1]];  (* A298751 *)

Prog

(PARI) (1+sqrt(4*sqrt(5)-3))/2 \\ Charles R Greathouse IV, May 18 2026

Crossrefs

Cf. A298749, A298750, A298752.

Sequence in context: A375192 A019661 A200130 * A284151 A370467 A164003

Adjacent sequences: A298748 A298749 A298750 * A298752 A298753 A298754

Keyword

nonn,easy,cons,changed

Author

Clark Kimberling, Feb 13 2018

Status

approved