74618domain: NAppears in sequencesSecond entry in row n of triangle in A169950.at n=33A169952Number of connected matchings with n crossings, in a disk.at n=7A232222a(n) = time to the nearest second at the n-th instant (n>=0) when the hour and minute hands on a clock face coincide, starting at time 0:00.at n=19A335789