75060domain: NAppears in sequencesNumber of permutations of length n which avoid the patterns 321, 1342, 3124.at n=22A116718Exponential (2,4)-perfect numbers: numbers m such that esigma(esigma(m)) = 4m, where esigma(m) is the sum of exponential divisors of m (A051377).at n=35A328133