Motivated by a problem proposed by Seiffert a quarter of century ago, we explicitly evaluate binomial sums with Pell and Lucas polynomials as weight functions. Their special cases result in several interesting identities concerning Fibonacci and Lucas numbers.

An SEIV epidemic model for childhood disease with partial permanent immunity is studied. The basic reproduction numberR0has been worked out. The local and global asymptotical stability analysis of the equilibria are performed, respectively. Furthermore, if we take the treated rateτas the bifurcation parameter, periodic orbits will bifurcate from endemic equilibrium whenτpasses through a critical value. Finally, some numerical simulations are given to support our analytic results.

By examining Fourier–Legendre series pairs $\mathcal{F}\left(y\right)$ and $\mathcal{G}\left(y\right)$, fifteen classes of symmetric and asymmetric bivariate series will systematically be investigated. A compendium of 360 remarkable summation formulae will be established. They may serve as a complementary work to the paper by Chu and Campbell (The Ramanujan Journal (2023)).