Original poster: Mddeming-at-aol-dot-com In a message dated 3/14/04 11:48:12 AM Eastern Standard Time, tesla-at-pupman-dot-com writes: > is approximated by (-1)^(n+1) 2^(1/2) (4n-1)^(-1/2). It is curious that you use "(-1)^(n+1)", which will always be equal to -1. Why is that? Uhhhh, When I was in school, (-1)^(n+1) was negative only when n is even. ;-) Matt D.