A296182 Decimal expansion of (2 + phi)/2, with the golden section phi from A001622.

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

Offset

1,2

Comments

In a regular pentagon this is the distance between a vertex and the midpoint of the opposite side in units of the radius of the circumscribing circle.

Links

Table of n, a(n) for n=1..99.

Formula

Equals (2 + phi)/2 = (5 + sqrt(5))/4 = (2*phi - 1)*phi/2 = with phi from A001622.

Equals 1 + A019863.

From Amiram Eldar, Nov 28 2024: (Start)

Equals 1/A322159.

Equals Product_{k>=0} (1 + 1/A081003(k)). (End)

Example

1.809016994374947424102293417182819058860154589902881431067724311352630231409451...

Mathematica

RealDigits[(5 + Sqrt[5])/4, 10, 111][[1]] (* Robert G. Wilson v, Jan 14 2018 *)

Prog

(PARI) (5 + sqrt(5))/4 \\ Michel Marcus, Jan 08 2018

Crossrefs

Cf. A001622, A019863, A081003, A322159.

Sequence in context: A076350 A197617 A005076 * A019863 A350747 A243456

Adjacent sequences: A296179 A296180 A296181 * A296183 A296184 A296185

Keyword

nonn,cons,easy

Author

Wolfdieter Lang, Jan 08 2018

Status

approved