TY - JOUR ID - Bunge2018 LB - Bunge2018 AU - Bunge, Ryan C. AU - DeShong, Steven AU - El-Zanati, Saad I. AU - Fischer, Alexander AU - Roberts, Dan P. AU - Teng, Lawrence TI - The spectrum problem for digraphs of order 4 and size 5 ST - The spectrum problem for digraphs of order 4 and size 5 JO - Opuscula Math. JA - Opuscula Math. JF - Opuscula Mathematica PY - 2018 VL - 38 IS - 1 SP - 15 EP - 30 DO - https://doi.org/10.7494/OpMath.2018.38.1.15 UR - https://doi.org/10.7494/OpMath.2018.38.1.15 AB - The paw graph consists of a triangle with a pendant edge attached to one of the three vertices. We obtain a multigraph by adding exactly one repeated edge to the paw. Now, let \(D\) be a directed graph obtained by orientating the edges of that multigraph. For 12 of the 18 possibilities for \(D\), we establish necessary and sufficient conditions on \(n\) for the existence of a \((K^{*}_{n},D)\)-design. Partial results are given for the remaining 6 possibilities for \(D\). KW - spectrum problem KW - digraph decompositions SN - 1232-9274 ER -