Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10.2 9/5/84; site philabs.UUCP Path: utzoo!watmath!clyde!cbosgd!ihnp4!houxm!vax135!cornell!uw-beaver!tektronix!hplabs!hao!seismo!cmcl2!philabs!dpb From: dpb@philabs.UUCP (Paul Benjamin) Newsgroups: net.math Subject: Re: Re: Self-generating power series? Message-ID: <225@philabs.UUCP> Date: Fri, 1-Feb-85 14:36:44 EST Article-I.D.: philabs.225 Posted: Fri Feb 1 14:36:44 1985 Date-Received: Wed, 6-Feb-85 01:54:38 EST References: <1155@ihuxi.UUCP> <1263@ut-ngp.UUCP> Organization: Philips Labs, Briarcliff Manor, NY Lines: 47 > > Can anyone find a (nontrivial) power series that, evaluated over the > > nonnegative integers, gives its own coefficients? That is, > > > > oo n > > --- A * x > > \ n > > P(x) = / ------- = A for n >= 0 > > --- n! n > > k=0 > > > > Chris Scussel > > AT&T Bell Labs > > ihnp4!ihuxi!trough > > Surely you mean P(n)=, as in: > oo n > --- A * x > \ n > P(n) = / ------- = A for n >= 0 > --- n! n > k=0 > > -- > > John L. Templer > University of Texas at Austin > > {allegra,gatech,seismo!ut-sally,vortex}!ut-ngp!lindley > > "and they called it, yuppy love." Even more surely you mean: oo k --- A * n \ k P(n) = / ------- = A for n >= 0 --- k! n k=0 0 A * 0 0 0 Since P(0) = ------- + (zeros) = 0 (if 0 is defined as 0), 0! we can change the lower limit of summation to 1.