On Simple Characterisations of Sheffer psi- polynomials and Related Propositions of the Calculus of Sequences
<|reference_start|>On Simple Characterisations of Sheffer psi- polynomials and Related Propositions of the Calculus of Sequences: A calculus of sequences started in 1936 opened the way for future extensions of umbral calculus in its finite operator form. Because of historically established notation we call it the psi-calculus.It appears in parts to be almost automatic extension of the standard classical finite operator calculus.<|reference_end|>
@article{kwasniewski2003on,
    title={On Simple Characterisations of Sheffer psi- polynomials and Related
  Propositions of the Calculus of Sequences},
    author={A. K. Kwasniewski},
    journal={Bull. Soc. Sci. Lett. Lodz Ser. Rech. Deform. 52, Ser. Rech.
  Deform. 36 (2002) pp.45-65},
    year={2003},
    archivePrefix={arXiv},
    eprint={math/0312397},
    primaryClass={math.CO cs.DM}
}