A123732 Decimal expansion of Sum_{m>=1} (-1)Sigma(m)/m^3.

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

Offset

1,2

Comments

The sum over (-1)Sigma(m)/m^2 is divergent.

Links

Table of n, a(n) for n=1..105.

Formula

Equals Sum_{m>=1} A049060(m)/m^3.

Equals Product_{p prime} (1 + (p^3-p^2+1)/((p-1)^2*(p+1)*(p^2+p+1))). - Amiram Eldar, Aug 26 2022

Example

1.46400354360318202593842489434542708983961995794945...

Prog

(PARI) prodeulerrat(1 + (p^3-p^2+1)/((p-1)^2*(p+1)*(p^2+p+1))) \\ Amiram Eldar, Aug 26 2022

Crossrefs

Cf. A049060, A123733, A123734, A183699.

Sequence in context: A274926 A079171 A029678 * A244339 A253623 A227436

Adjacent sequences: A123729 A123730 A123731 * A123733 A123734 A123735

Keyword

nonn,cons

Author

Yasutoshi Kohmoto, Nov 18 2006

Extensions

40 more digits from R. J. Mathar, Dec 19 2010

More terms from Amiram Eldar, Aug 26 2022

Status

approved