A258716 Decimal expansion of 3 + 2*Sum_{k>=0} 1/Product_{i=0..k} (2^(2^i) - 1).

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

Offset: 1

Author

N. J. A. Sloane, Jun 15 2015

Keywords

• nonn
• cons

Examples

			5.7112854057096334466665254291814791046797658771989754...
		

Links

• Gary W. Adamson and N. J. A. Sloane, Correspondence, May 1994, including Adamson's MSS "Algorithm for Generating nth Row of Pascal's Triangle, mod 2, from n", and "The Tower of Hanoi Wheel". Defines this number.

Crossrefs

Cf. A215016, A258714, A258715.

Programs

Mathematica

RealDigits[2/NProduct[1 - 1/2^(2^k), {k, 0, Infinity}, WorkingPrecision -> 120]][[1]] (* Amiram Eldar, Feb 19 2024 *)

PARI

2/prodinf(k = 0, 1 - 1/2^(2^k)) \\ Amiram Eldar, Feb 19 2024

Formula

Equals 3 + A258715.

From Amiram Eldar, Feb 19 2024: (Start)

Equals 2 * A258714 + 3.

Equals 2/A215016. (End)