The Converse of Abel's Theorem on Power Series

J. E. Littlewood
1911 Proceedings of the London Mathematical Society  
O.S.," p. 3 i i . t This generalised method of summation is due to Riesz, Comptes Rendus, July 5th, 1909. Cesaro's first mean has 1 in place of fin: if this mean exists we say that 2a» is summable (Cl). The notation (Cr), R (r, fi n ) was introduced by Hardy.
doi:10.1112/plms/s2-9.1.434 fatcat:nq3wt62fpfhn5jmikouz4e5lri