 During his first two years , ML Pin studied Pali and Sanskrit at the University of London School of Oriental and African Studies and lived with Mr and Mrs L J Marshall of 23 Portland Place in Brighton , from whom he also received additional instruction in mathematics , English , and French . Such was his talent in mathematics that Mr Marshall , who was head of Mathematics and Surveying at Brighton Technical College , wrote to the Superintendent of Siamese Government Students recommending that ML Pin major in mathematics instead and saying that his skills would undoubtedly warrant a university scholarship for mathematical studies . This , however , did not suit the requirements of the Ministry of Public Instruction , and so ML Pin did not continue his mathematics education . Nevertheless , his interest in the field did not waver , and he continued to produce works on the subject . Among these are his publication in 1927 in <unk> Sara , the journal of <unk> <unk> ( the Thai Association in the UK ) , of a formula which he called the " Everlasting Calendar " , upon which he later based the development of a set of slide rules which could be used to calculate the day of week for any given date , and his publication of Miscellaneous Problems , a collection of various mathematical problems he had worked on , later in 1960 . 
