Can large earthquakes happen twice/thrice at the same place within a short timeframe
Aftershocks after a major earthquake can occur for a period of weeks after the initial major earthquake, but the magnitude of the aftershocks is always less than that of the initial major quake. The paper History of Earthquakes of India &amp; the Himalayas discusses the each of the major earthquakes in the region for the last 200 years. Information on earthquakes before 1800 is patchy. The earthquakes discussed are the ones that occurred in: 1803, 1833, 1869, 1897 &amp; 1905.

Nothing was mentioned about a second or third major earthquake happening shortly after a major earthquake; even for the devastating 1934 earthquake.

Due to the different tectonic settings and causes for earthquakes in different parts of the world it is best not to look at the history of one part of the world and assume the same will occur elsewhere. The expectancy of earthquakes and their patterns in the Himalayas should not be compared with earthquakes in Japan, New Zealand, western USA, Turkey or elsewhere.