An explicit formula is obtained for the coefficients of the cyclotomic polynomial Fn(x), where n is the product of two distinct odd primes.A recursion formula and a lower bound and an improvement of Bang’s upper bound for the coefficients of Fn(x) are also obtained, where n is the product of three distinct primes.The cyclotomic coefficients are also studied when n is the product of four distinct odd primes.A recursion formula and upper bounds for its coefficients are obtained.The last chapter includes a different approach to the cyclotomic coefficients.A connection is obtained between a certain partition function and the cyclotomic coefficients when n is the product of an arbitrary number of distinct odd primes.Finally, an upper bound for the coefficients is derived when n is the product of an arbitrary number of distinct and odd primes.
