login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A308716 Decimal expansion of 2*sinh(Pi/2)/Pi. 4
1, 4, 6, 5, 0, 5, 2, 3, 8, 3, 3, 3, 6, 6, 3, 4, 8, 7, 7, 6, 0, 9, 1, 7, 9, 3, 7, 4, 1, 1, 2, 6, 5, 1, 0, 0, 7, 8, 1, 9, 9, 3, 4, 2, 6, 4, 1, 6, 7, 3, 4, 0, 8, 7, 1, 8, 3, 9, 5, 9, 0, 9, 1, 2, 3, 2, 5, 3, 9, 7, 3, 8, 5, 9, 5, 3, 6, 8, 7, 2, 1, 6, 5, 9, 9, 2, 8, 8, 7, 4, 2, 8, 7, 1, 0, 7, 5, 8, 6, 0, 0, 1, 9, 5, 1, 8, 7, 3, 4, 1, 8, 3, 0, 4, 3, 1, 5, 6, 9, 8 (list; constant; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..120.

FORMULA

Equals Product_{k>=1} (1 + 1/(4*k^2)).

Equals Product_{k>=1} (1 + 1/A016742(k)).

Equals binomial(0, i/2), where i is the imaginary unit. - Amiram Eldar, Nov 25 2020

EXAMPLE

1.465052383336634877609179374112651007819934264167...

MATHEMATICA

RealDigits[2 Sinh[Pi/2]/Pi, 10, 120][[1]]

PROG

(PARI) 2*sinh(Pi/2)/Pi \\ Michel Marcus, Jun 20 2019

CROSSREFS

Cf. A016742, A060294, A156648, A308715.

Sequence in context: A019089 A173462 A019123 * A021219 A200127 A222069

Adjacent sequences:  A308713 A308714 A308715 * A308717 A308718 A308719

KEYWORD

nonn,cons

AUTHOR

Ilya Gutkovskiy, Jun 19 2019

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified April 20 05:46 EDT 2021. Contains 343121 sequences. (Running on oeis4.)