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A231902 Decimal expansion of Pi/4 + log(2)/2. 1
1, 1, 3, 1, 9, 7, 1, 7, 5, 3, 6, 7, 7, 4, 2, 0, 9, 6, 4, 3, 2, 4, 2, 7, 6, 9, 0, 6, 5, 4, 8, 9, 6, 4, 0, 0, 5, 0, 8, 7, 0, 4, 2, 4, 1, 7, 0, 2, 3, 9, 0, 4, 0, 8, 2, 3, 0, 4, 0, 7, 6, 1, 5, 2, 8, 2, 3, 6, 5, 0, 9, 1, 2, 5, 5, 6, 3, 9, 9, 6, 0, 7, 4, 5, 9, 9, 4 (list; constant; graph; refs; listen; history; text; internal format)
OFFSET

1,3

REFERENCES

L. B. W. Jolley, Summation of series, Dover Publications Inc. (New York), 1961, p. 28 (formula 154).

LINKS

Ivan Panchenko, Table of n, a(n) for n = 1..1000

FORMULA

Equals 1 + Sum_{m>=1} -(-1)^m/(2m*(2m+1)) = 1 + 1/(2*3) - 1/(4*5) + 1/(6*7) - 1/(8*9) + ...

EXAMPLE

1.131971753677420964324276906548964005087042417023904082304076152823650...

MATHEMATICA

RealDigits[Pi/4 + Log[2]/2, 10, 90][[1]]

PROG

(PARI) default(realprecision, 100); (Pi + 2*log(2))/4 \\ G. C. Greubel, Aug 24 2018

(MAGMA) SetDefaultRealField(RealField(100)); R:=RealField(); (Pi(R) + 2*Log(2))/4 // G. C. Greubel, Aug 24 2018

CROSSREFS

Cf. A003881: Pi/4; A016655: 10*(log(2)/2); A006752: Catalan's constant; A072691: Pi^2/12.

Sequence in context: A052931 A006803 A197730 * A143495 A245789 A210395

Adjacent sequences:  A231899 A231900 A231901 * A231903 A231904 A231905

KEYWORD

nonn,cons

AUTHOR

Bruno Berselli, Nov 15 2013

STATUS

approved

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Last modified April 25 18:12 EDT 2019. Contains 322461 sequences. (Running on oeis4.)