A054400 Decimal expansion of 4 * Product_{i=1..inf} (1-3/(2*(i+1)))^(1/2^i).

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

Offset

1,2

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=1..105.

Example

1.52675335335...

Mathematica

digits = 105; 4*NProduct[ (1-3/(2*(i+1)))^(1/2^i), {i, 1, Infinity}, WorkingPrecision -> digits+5, NProductFactors -> 4*digits] // RealDigits[#, 10, digits]& // First (* Jean-François Alcover, Mar 07 2013 *)

Crossrefs

4*A054399.

Sequence in context: A363238 A021659 A011506 * A377645 A035568 A344964

Adjacent sequences: A054397 A054398 A054399 * A054401 A054402 A054403

Keyword

nonn,easy,cons

Author

N. J. A. Sloane, May 22 2000

Extensions

More terms from David Wasserman, Mar 04 2002

Status

approved