Maximizing weighted sums of binomial coefficients using generalized continued fractions
S. P. GlasbyG. R. Paseman
所有作者
S. P. GlasbyG. R. Paseman
文献摘要
Let m,r∈Z and ω∈R satisfy 0⩽r⩽m and ω⩾1. Our main result is a generalized continued fraction for an expression involving the partial binomial sum sm(r)=∑i=0r(im). We apply this to create new upper and lower bounds for sm(r) and thus for gω,m(r)=ω−rsm(r). We also bound an integer r0∈{0,1,…,m} such that gω,m(0)<⋯<gω,m(r0−1)⩽gω,m(r0) and gω,m(r0)>⋯>gω,m(m). For real ω⩾3 we prove that r0∈{⌊ω+1m+2⌋,⌊ω+1m+2⌋+1}, and also r0=⌊ω+1m+2⌋ for ω∈{3,4,…} or ω=2 and 3∤m.