A lower bound for A350155 can be optained with the pattern below. A350155(n) >= 3 * 2^n - 6 Mirrors are shown as '\' or '/', empty locations are '.', and the starting location of the laser is 'V'. Found by Benjmain Butin. 20th January 2022. Example for a grid of size 10, 3066 its. V \\......\\ .\\....\\. ..\\..\\.. ...\\\\... ....\\.... ...\\//... ..\\..//.. .\\....//. \\......// \......../ Example for a grid of size 11, 6138 hits. V \\.......\\ .\\.....\\. ..\\...\\.. ...\\.\\... ....\\\.... ....\\/.... ...\\.//... ..\\...//.. .\\.....//. \\.......// \........./