31619domain: NAppears in sequencesa(n) = ((n-1)^n/n)*Sum_{k>=1} (k^n/n^k).at n=5A086914Numbers k such that k and k^2 use only the digits 1, 3, 6, 7 and 9.at n=19A137039Iterates of f(x)=floor((3x-1)/2) from x=6.at n=22A183208Number of partitions of n into exactly 7 different parts with distinct multiplicities.at n=21A212118