Hermite constant [SEP] named after
Hermite constant
In mathematics, the Hermite constant, named after Charles Hermite, determines how short an element of a lattice in Euclidean space can be.
The constant "γ" for integers "n"  0 is defined as follows. For a lattice "L" in Euclidean space R unit covolume, i.e. vol(R/"L") = 1, let "λ"("L") denote the least length of a nonzero element of "L". Then is the maximum of "λ"("L") over all such lattices
Appell sequence
In mathematics, an Appell sequence, named after Paul Émile Appell, is any polynomial sequence formula_1 satisfying the identity
and in which formula_3 is a non-zero constant.
Among the most notable Appell sequences besides the trivial example formula_4 are the Hermite polynomials, the Bernoulli polynomials, and the Euler polynomials. Every Appell sequence is a Sheffer sequence, but most Sheffer sequences are not Appell sequences.
Equivalent characterizations of Appell sequences.
The following conditions on polynomial sequences can easily be seen to be equivalent