The edge spectral extremal problem for odd wheels in nonzero residue classes

Honghao Chen, Jing Gao, Shuchao Li

For a fixed integer $k\ge 2$, let $W_{2k+1}=K_1\vee C_{2k}$ be an odd wheel graph. The fixed-size spectral extremal problem aims to determine \[ \operatorname{spex}(m,W_{2k+1}):=\m…