General Nörlund transforms and power series methods.
Generalized strong summability of infinite series.
Inäquivalenzsätze in der Limitierungstheorie.
Inclusion results for convolution submethods.
Iteration Products of Methods of Summability and Natural Scales.
Mémoire sur les séries divergentes
Multisummability for some classes of difference equations
This paper concerns difference equations where takes values in and is meromorphic in in a neighborhood of in and holomorphic in a neighborhood of 0 in . It is shown that under certain conditions on the linear part of , formal power series solutions in are multisummable. Moreover, it is shown that formal solutions may always be lifted to holomorphic solutions in upper and lower halfplanes, but in general these solutions are not uniquely determined by the formal solutions.
Multisummability of formal power series solutions of nonlinear meromorphic differential equations
In this paper a proof is given of a theorem of J. Écalle that formal power series solutions of nonlinear meromorphic differential equations are multisummable.
Note on a scale of Abel-type summability methods.
On Abel summability of multiple Jacobi series
On Abel-type methods of summability.
On summability of Fourier series.
On strong summability.
On the approximation by Euler, Borel and Taylor means in enlarged Hölder classes
We generalize and improve in some cases the results of Mahapatra and Chandra [7]. As a measure of Hölder norm approximation, generalized modulus-type functions are used.
On the approximation of function by Robel matrix
On the relation between the Borel sum and the classical solution of the Cauchy problem for certain partial differential equations
On the weak Borel property of methods of summation
Ordre, convergence et sommabilité de produits de séries de Dirichlet
L’article donne des réponses optimales ou presque optimales aux questions suivantes, qui remontent à Stieltjes, Landau et Bohr, et concernent des séries de Dirichlet
Pointwise limit theorem for a class of unbounded operators in -spaces
We distinguish a class of unbounded operators in , r ≥ 1, related to the self-adjoint operators in ². For these operators we prove a kind of individual ergodic theorem, replacing the classical Cesàro averages by Borel summability. The result is equivalent to a version of Gaposhkin’s criterion for the a.e. convergence of operators. In the proof, the theory of martingales and interpolation in -spaces are applied.
Résurgence quantique