Hello, I looked at your number in my tables : niet, I have 3.216 billions on disk here and 2.83 billion on static tables at the uqam site : nothing found. (I do have results but they are too far fetch to be considered). but... the identify function in Maple 13, found this :
identify(8.525024664, all); 1/2 7 3 ------ + 1/2 Zeta(3) + 9/5 exp(1) 4
ef(%); 8.52502465606
7/4*3^(1/2)+1/2*Zeta(3)+9/5*exp(1) well, if we play around with the Digits settings and the <all> option of that function then : arctan(-8/9*2^(1/2)+16/5*ln(2)+1/6*ln(3)) = 0.852502466428 What is the confortable precision of your result ? best regards, simon plouffe