House Number Puzzle; Pell’s Equation; Continued Fraction; Convergents.
One of the most significant mathematicians of India, of 20th century was Srinivasa Ramanujan. He posed several interesting puzzles as his notebook jottings. The entries of his notebooks were today considered to be mathematical treasures. During the period when Ramanujan stayed at Trinity College of Cambridge University, England his Indian friend posed a interesting puzzle which Ramanujan had solved immediately. In this paper, I will introduce that puzzle and provide the way as how Ramanujan could have accomplished the solution in a flash.
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 R. Sivaraman, Recognizing Ramanujan’s House Number Puzzle, German International Journal of Modern Science, 22, November 2021, pp. 25 – 27.
Received : 21 September 2021
Accepted : 10 February 2022
Published : 27 February 2022