Integer Assumptions in Integrations

*To*: mathgroup at smc.vnet.net*Subject*: [mg20153] Integer Assumptions in Integrations*From*: "Will Cooper" <wcooper1 at san.rr.com>*Date*: Sat, 2 Oct 1999 03:05:09 -0400*Organization*: Time Warner Cable of San Diego, CA*Sender*: owner-wri-mathgroup at wolfram.com

Hello, How can I set a variable assumption to be an integer in an integration calculation? e.g. The incomplete gamma function is defined as Gamma[a,q] = Integrate[t^(a-1)*Exp[-t], {t, q, Infinity}] I want to set the assumption that 'a' is always an Integer. I don't want to round 'a' to the next lowest integer, i.e. Integrate[t^(Integer[a]-1)*Exp[-t], {t, q, Infinity}] I just want to indicate that 'a' only assumes integer values. Thanks for any assistance. Will Cooper.