A145431 Decimal expansion of Sum_{n>=1} n^3/binomial(2n,n).

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

Offset

1,1

References

Alexander Apelblat, Tables of Integrals and Series, Harri Deutsch, 1996, 4.1.37.

Links

Table of n, a(n) for n=1..93.

Formula

Equals (2/243)*(405+37*Pi*sqrt(3)).

Example

4.990384604362124...

Maple

10/3+74/243*Pi*3^(1/2);

Mathematica

RealDigits[2*(405+37*Pi*Sqrt[3])/243, 10, 120][[1]] (* Amiram Eldar, Aug 23 2024 *)

Crossrefs

Cf. A000984, A304656.

Sequence in context: A145521 A379126 A230979 * A196516 A021671 A359187

Adjacent sequences: A145428 A145429 A145430 * A145432 A145433 A145434

Keyword

cons,easy,nonn

Author

R. J. Mathar, Feb 08 2009

Status

approved