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A190357 Decimal expansion of 1/4 - 2/Pi^2. 1
0, 4, 7, 3, 5, 7, 6, 3, 2, 7, 1, 5, 3, 2, 4, 4, 5, 7, 1, 1, 2, 2, 4, 1, 0, 7, 3, 5, 8, 0, 5, 4, 4, 7, 2, 2, 1, 9, 1, 2, 8, 2, 4, 5, 0, 6, 5, 5, 5, 0, 6, 9, 0, 2, 3, 0, 8, 7, 8, 1, 9, 3, 6, 2, 1, 1, 6, 5, 3, 7, 5, 8, 0, 7, 5, 5, 2, 9, 1, 1, 7, 6, 1, 7, 5, 8, 1, 4, 5, 2, 1, 4, 8, 7, 5, 6, 3, 2, 4, 7, 7 (list; constant; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

Constant given on p. 1 of Schlage-Puchta.

LINKS

G. C. Greubel, Table of n, a(n) for n = 0..10000

Jan-Christoph Schlage-Puchta, Sumsets avoiding squarefree integers, arXiv:1105.1305 [math.NT], May 6, 2011.

FORMULA

Equals (1/4) - (2/Pi^2).

EXAMPLE

0.047357632715324457112241...

MATHEMATICA

Join[{0}, RealDigits[(1/4) - (2/Pi^2), 10, 100][[1]]] (* G. C. Greubel, Apr 05 2018 *)

PROG

(PARI) (1/4) - (2/Pi^2) \\ G. C. Greubel, Apr 05 2018

(MAGMA) R:=RealField(100); [(1/4) - (2/Pi(R)^2)]; // G. C. Greubel, Apr 05 2018

CROSSREFS

Cf. A005117, A010716 (1/18), A059956 (6/Pi^2).

Sequence in context: A241026 A198743 A271798 * A296499 A199446 A100127

Adjacent sequences:  A190354 A190355 A190356 * A190358 A190359 A190360

KEYWORD

nonn,easy,cons

AUTHOR

Jonathan Vos Post, May 09 2011

STATUS

approved

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Last modified August 24 03:20 EDT 2019. Contains 326260 sequences. (Running on oeis4.)