Fig. 7
From: CHOP: haplotype-aware path indexing in population graphs
A pair of nodes u and v where |uS|≥k−1 and |vS|≥k−1. Note that extension is only possible by prefixing v with the right-hand flanking substring of u, given that out(u)>1. The extension operation denoted as \(u \twoheadrightarrow v\) is defined as vS=uS[|uS|−k−1,|uS|]⋯vS