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A156648 Decimal expansion of prod_{k>=1} (1+1/k^2). 6
3, 6, 7, 6, 0, 7, 7, 9, 1, 0, 3, 7, 4, 9, 7, 7, 7, 2, 0, 6, 9, 5, 6, 9, 7, 4, 9, 2, 0, 2, 8, 2, 6, 0, 6, 6, 6, 5, 0, 7, 1, 5, 6, 3, 4, 6, 8, 2, 7, 6, 3, 0, 2, 7, 7, 4, 7, 8, 0, 0, 3, 5, 9, 3, 5, 5, 7, 4, 4, 7, 3, 2, 4, 1, 1, 1, 0, 2, 2, 0, 7, 3, 2, 1, 3, 2, 5, 5, 9, 2, 6, 5, 9, 0, 3, 2, 3, 0, 2, 3, 5, 2, 8, 7, 5 (list; constant; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Square root of A084243.

REFERENCES

Reinhold Remmert, Classical topics in complex function theory, Vol. 172 of Graduate Texts in Mathematics, p. 12, Springer, 1997.

LINKS

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

FORMULA

Equals sinh(Pi)/Pi.

Equals 1/A090986. - R. J. Mathar, Mar 05 2009

Binomial(2, 1+i) = 1/(i!*(-i)!) (where x! means Gamma(x+1)). - Robert G. Wilson v, Feb 23 2015

EXAMPLE

Equals 3.676077910374977720695697492028260666507156346827630277478003593557447324111... = (1+1)*(1+1/4)*(1+1/9)*(1+1/16)*(1+1/25)*...

MAPLE

evalf(sinh(Pi)/Pi) ;

MATHEMATICA

RealDigits[ Sinh[Pi]/Pi, 10, 111][[1]] (* or *)

RealDigits[ Re[ 1/(I!*(-I)!)], 10, 111][[1]] (* Robert G. Wilson v, Feb 23 2015 *)

PROG

(PARI) sinh(Pi)/Pi \\ Charles R Greathouse IV, Dec 16 2013

CROSSREFS

Cf. A073017, A258870, A258871.

Sequence in context: A228787 A245220 A165952 * A278688 A016616 A256936

Adjacent sequences:  A156645 A156646 A156647 * A156649 A156650 A156651

KEYWORD

cons,easy,nonn

AUTHOR

R. J. Mathar, Feb 12 2009

STATUS

approved

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Last modified December 8 06:50 EST 2016. Contains 278902 sequences.