Re: [math-fun] Re^2: FW: A conjectural series for 1/pi of a new type

27 Jan 2011


      * Bill Gosper <billgosper@gmail.com> [Jan 27. 2011 13:56]:
...
Simon>hello everybody,
about that formula for 1/pi,
SP>it is nice , the coefficient a(k) is
a binomial term
SP>The sequence a(k) is :
1, 1, 33, 97, 1729, 8001, 105441, 627873,
     6989697, 48363649, 488206753,
     3701949153, 35289342529,
     283146701761, 2610495177057,
     21695983405857, 196218339243777,
     1667338615773441, 14917038493453089,
     128562758660255073,
     1143482133220664769,
     9946278255903268929,
     88205310329762729697,
     771946983805271894433,
     6837125121111415598721,...
SP>a(k] has this g.f.
               1
      -------------------- =
                     2 1/2
      (1 - 2 x - 63 x )
How did you get this?
Let me guess:  http://oeis.org/A098441
...
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Re: [math-fun] Re^2: FW: A conjectural series for 1/pi of a new type

Joerg Arndt