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A156648 Decimal expansion of prod_{k>=1} (1+1/k^2). 2
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. [From R. J. Mathar, Mar 05 2009]

EXAMPLE

3.676077910374977720 = (1+1)*(1+1/4)*(1+1/9)*(1+1/16)*(1+1/25)*...

MAPLE

evalf(sinh(Pi)/Pi) ;

PROG

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

CROSSREFS

Sequence in context: A228787 A245220 A165952 * A016616 A021276 A067753

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 August 1 05:43 EDT 2014. Contains 245104 sequences.