We study thermodynamics of an ideal gas in Doubly Special Relativity. New
type of special functions (which we call Incomplete Modified Bessel functions)
emerge. We obtain a series solution for the partition function and derive
thermodynamic quantities. We observe that DSR thermodynamics is
non-perturbative in the SR and massless limits. A stiffer equation of state is
found.Comment: 14 pages, 10 figure