1350001domain: NPropertiesPrimalityPrimeyesAppears in sequencesphi(n) is equal to the product of the dual prime-power components of n-1 (i.e., A008477(n-1)).at n=9A039783Primes q such that Sum_(q-1; i=1..m) e(i)/p(i) is an integer k, where the prime factorization of n is Product_(n; i=1..m) p(i)^e(i).at n=8A267143Prime numbersat n=103545