Number of multisets E(n) generable by the following procedure: E(0) = { 0, 0, ... }; to get an E(n+1) from an E(n), first increment all elements then optionally choose an x and a y and replace them with 0 and x+y.

A378734

Number of multisets E(n) generable by the following procedure: E(0) = { 0, 0, ... }; to get an E(n+1) from an E(n), first increment all elements then optionally choose an x and a y and replace them with 0 and x+y.