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by Shyam Sunder Gupta (Author)
Back Jacket
This book is a great treasure for everyone who enjoys the beauty of the fascinating world of recreational mathematics. It focuses on recreational aspects of numbers to create interest and motivate readers to learn to be creative in improving their problem-solving techniques. The book would help ignite interest in numbers, which will benefit teachers trying to teach math, especially to students who don't like math, by supplementing their regular curriculum with the module containing material from the book, which provides an opportunity for fun and joy while developing mathematical skills. The ideas for further exploration given in the book offer food for thought to delve into the world of research and fun, in addition to testing computational skills. The book communicates the excitement and fascination of numbers to the students in schools and colleges. The theory behind the subject matter has been kept to a minimum to retain the recreational nature of the book. The book has a delightful coverage of numerical curiosities, coincidences and wonders, revealing many new eye-opening properties of numbers.
Organized into 23 chapters, the book contains a large variety of topics: digital root wonders, the elegance of squares, triangular numbers, Smith numbers, amicable numbers, perfect, multiple perfect and sociable numbers, happy numbers, Fibonacci numbers, Lucas numbers, and the Golden ratio, Kaprekar numbers, self-numbers, repunit numbers, equal product of reversible numbers (EPRNs), rare numbers, fascinating factorials, Ulam numbers, mystery of π, cab and vampire numbers, digital invariants and narcissistic numbers, special numbers like autobiographical numbers, Harshad numbers, parasite numbers, polydivisible numbers, Ramanujan numbers, number curiosities such as lucky mistakes, Pascal's triangle and Pythagorean triplets. Pythagoras attributed mystical qualities to some of the numbers. Even the religious properties of numbers were extensively studied. So, four chapters are exclusively devoted to such numbers, namely, the amazing number 108, the unlucky 13, the beauty of 153, and the number of the beast, with lots of new curiosities and miraculous coincidences.
Author Biography
Shyam Sunder Gupta is a former senior officer of the Government of India and spearheaded multiple complex projects as Principal Chief Engineer of Indian Railways. He is an Indian Railway Service of Engineers (IRSE) officer of batch 1981. He has more than 35 years of experience in various managerial, administrative and technical positions, such as Principal Chief Engineer, Executive Director and Divisional Railway Manager on Indian Railways. An Indian recreational mathematician who is actively involved in popularising mathematics at the national and international levels. His major discoveries are Equal Product of Reversible Numbers (EPRNs), rare numbers, unique numbers, palindromic pseudoprimes, fifth-order prime polynomial, 17350-digit memorable prime, etc.
His interest in number recreations dates back to 1978, when his first paper, Miracles of Last Digit, was published. Since then, his contributions have been published in Science Reporter, Science Today, Math Education, At Right Angles, The American Mathematical Monthly, The Mathematical Gazette, Mathematical Spectrum, Scientia Magna and several international books like Unsolved Problems in Number Theory (by R. K. Guy), The Universal Book of Mathematics (by David J. Darling), The Penguin Dictionary of Curious and Interesting Numbers (by David Wells), Prime Curios!: The Dictionary of Prime Number Trivia (by Chris K. Caldwell and G. L. Honaker) and Those Fascinating Numbers (by Jean-Marie De Koninck). Author of the book, Creative Puzzles to Ignite Your Mind (Springer, 2023), he also co-authored Civil Engineering Through Objective Type Questions (CBS, 1985).
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