A334367 Decimal expansion of Sum_{k>=0} 1/(4*k+2)!!.

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

Offset: 0

Author

Ilya Gutkovskiy, Apr 24 2020

Keywords

• nonn
• cons

Comments

This constant is transcendental.

Examples

			1/(2^1*1!) + 1/(2^3*3!) + 1/(2^5*5!) + ... = 0.52109530549374736162242...
		

Links

• Index entries for transcendental numbers

Crossrefs

Cf. A019774, A067626, A073742, A143280, A160327, A201504, A334366.

Programs

Mathematica

RealDigits[Sinh[1/2], 10, 110] [[1]]

PARI

sinh(1/2) \\ Michel Marcus, Apr 25 2020

Formula

Equals sinh(1/2).

Equals (1/2) * Product_{k>=1} 1 + 1/(2*k*Pi)^2. - Amiram Eldar, Jul 16 2020