A317202 Decimal expansion of 3 + (t^2+t^4)/2, where t = 0.543689... (A192918) is the real root of x^3 + x^2 + x = 1.

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

Offset: 1

Author

N. J. A. Sloane, Aug 05 2018

Keywords

• nonn
• cons

Comments

The minimal polynomial of this constant is 2*x^3 - 12*x^2 + 22*x - 13, and it is its unique real root. - Amiram Eldar, May 30 2023

Examples

			3.191487883953118747061354268227517293474691...
		

Links

• Bo Tan and Zhi-Ying Wen, Some properties of the Tribonacci sequence, European Journal of Combinatorics, 28 (2007) 1703-1719. See Theorem 4.5.

Crossrefs

Cf. A316711, A192918.

Programs

Mathematica

RealDigits[x /. FindRoot[2*x^3 - 12*x^2 + 22*x - 13, {x, 3}, WorkingPrecision -> 120]][[1]] (* Amiram Eldar, May 30 2023 *)