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A088454 Decimal expansion of 6/(Catalan*Pi^2). 6
6, 6, 3, 7, 0, 0, 8, 0, 4, 6, 1, 3, 8, 5, 3, 4, 6, 0, 7, 2, 1, 4, 3, 1, 6, 5, 7, 6, 1, 7, 0, 4, 8, 6, 9, 1, 3, 5, 8, 3, 9, 5, 7, 9, 6, 7, 7, 4, 8, 0, 8, 3, 8, 7, 2, 0, 6, 2, 0, 0, 9, 9, 0, 2, 8, 6, 6, 1, 3, 0, 2, 3, 1, 0, 1, 9, 6, 6, 4, 7, 7, 5, 0, 3, 3, 2, 2, 0, 4, 1, 0, 4, 6, 0, 3, 6, 6, 3, 9, 5, 0, 7 (list; constant; graph; refs; listen; history; text; internal format)
OFFSET

0,1

COMMENTS

This is the probability that a randomly chosen Gaussian integer (e.g., -2 + 5i) is squarefree (Pegg, 2003). - Alonso del Arte, Dec 20 2013

LINKS

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

Ed Pegg Jr., The Moebius Function

Eric Weisstein's World of Mathematics, Relatively Prime

Eric Weisstein's World of Mathematics, Squarefree

Eric Weisstein's World of Mathematics, Gaussian Integer

EXAMPLE

0.663700804613853460721431657617048691358...

MATHEMATICA

RealDigits[(6/Pi^2)/Catalan, 10, 100][[1]] (* Alonso del Arte, Dec 20 2013 *)

PROG

(PARI) 6/(Catalan*Pi^2) \\ G. C. Greubel, Aug 23 2018

(MAGMA) R:= RealField(100); 6/(Catalan(R)*Pi(R)^2); // G. C. Greubel, Aug 23 2018

CROSSREFS

Cf. A059956, A006752.

Sequence in context: A110632 A202068 A301974 * A095228 A021605 A180573

Adjacent sequences:  A088451 A088452 A088453 * A088455 A088456 A088457

KEYWORD

nonn,cons,easy

AUTHOR

Eric W. Weisstein, Sep 30 2003

STATUS

approved

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Last modified August 20 14:36 EDT 2019. Contains 326152 sequences. (Running on oeis4.)