508989domain: NAppears in sequencesFirst of a triple of consecutive integers, each the product of 4 distinct primes.at n=18A176167Number of arrangements of 4 nonzero numbers x(i) in -n..n with the sum of div(x(i),x(i+1)), where div(a,b)=a/b produces the integer quotient implying a nonnegative remainder, equal to zero.at n=23A190073