A054399 Decimal expansion of the constant Product_{i=1..inf} ((1-3/(2*(i+1)))^(1/2^i).

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

Offset

0,1

References

D.-Z. Du and F. K. Hwang, Combinatorial Group Testing and Its Applications, World Scientific, 2nd ed., 2000; p. 37.

Links

Table of n, a(n) for n=0..104.

Example

.381688338339685...

Mathematica

Exp[2*Derivative[1, 0][PolyLog][0, 1/2] - Derivative[0, 1, 0][LerchPhi][1/2, 0, 1/2]/2] // RealDigits[#, 10, 105]& // First (* Jean-François Alcover, Feb 19 2013 *)

Prog

(PARI)\p 500; prodinf(n=1, ((1-3/(2*(n+1)))^(1/2^n)))

Crossrefs

A054400/4.

Sequence in context: A247392 A219995 A021266 * A013676 A199270 A131563

Adjacent sequences: A054396 A054397 A054398 * A054400 A054401 A054402

Keyword

nonn,easy,cons

Author

N. J. A. Sloane, May 22 2000

Extensions

More terms from Jason Earls, Jun 28 2001

Status

approved