[seqfan] Re: A series for exp(Pi)

[Maximilian Hasler]

Seqfans,

as Oliver noticed (off line),
my one-liner implementing Richard's formula
did not produce the correct values
(obviously - the values were very odd in any sense !)

Exchanging the sinh and cosh fixes the bug:

a(n)=round(2^n*norm(gamma(n/2+3*I))*if(n%2,cosh(3*Pi),sinh(3*Pi))/Pi*3)

vector(20,n,a(n-1))
= [1, 6, 36, 222, 1440, 9990, 74880, 609390, 5391360, 51798150,
539136000, 6060383550, 73322496000, 951480217350, 13198049280000,
195053444556750, 3061947432960000, 50908949029311750,
894088650424320000, 16545408434526318750]

Thanks to Oliver for noticing the error and suggesting the bug fix.

Maximilian