A282823 Decimal expansion of Pi^2 + 8*K, where K is Catalan's constant.

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

Offset

2,2

Links

G. C. Greubel, Table of n, a(n) for n = 2..10000

Eric Weisstein's World of Mathematics, Polygamma Function (formula 24).

Sheldon Yang, Some properties of Catalan's constant G, Internat. J. Math. Ed. Sci. Tech. 23 (4) (1992) 549-556.

Formula

Equals 16*A222183.

Equals Psi(1, 1/4), where Psi(r, x) is the Polygamma function of order r.

Equals Sum_{k>=0} 1/(k + 1/4)^2. - Amiram Eldar, May 17 2022

Example

17.19732915450711073927131911933522402150689440149416770054533433319414...

Maple

Psi(1, 1/4) ; evalf(%) # R. J. Mathar, Dec 04 2024

Mathematica

RealDigits[Pi^2 + 8 Catalan, 10, 100][[1]]

Prog

(PARI) Pi^2 + 8*Catalan \\ Charles R Greathouse IV, Mar 04 2018
(PARI) zetahurwitz(2, 1/4) \\ Charles R Greathouse IV, Mar 04 2018
(Magma) SetDefaultRealField(RealField(100)); R:= RealField(); Pi(R)^2 + 8*Catalan(R); // G. C. Greubel, Aug 24 2018

Crossrefs

Cf. A000796, A006752, A222183, A282824.

Sequence in context: A199463 A086722 A296848 * A200500 A199669 A349580

Adjacent sequences: A282820 A282821 A282822 * A282824 A282825 A282826

Keyword

nonn,cons

Author

Bruno Berselli, Mar 06 2017

Status

approved