C++ :

#include <iostream>
#include <string>
using namespace std;

int nseq[20];

string mth_seq(int n, int m) {
  if (n == 0) return "";
  for (int j = 0; j < n; j++)
    if (nseq[n-j-1] * nseq[j] > m)
      return "E" + mth_seq(n-j-1, m/nseq[j]) + "S" + mth_seq(j, m%nseq[j]);
    else
      m -= nseq[n-j-1] * nseq[j];
}

main() {
  nseq[0] = 1;
  for (int i = 1; i <= 19; i++) {
    for (int j = 0; j < i; j++) nseq[i] += nseq[i-j-1] * nseq[j];
  }
  int N, M;
  while ((cin >> N && N) && (cin >> M && M)) {
    if (M-1 >= nseq[N-1])
      cout << "ERROR" << endl;
    else
      cout << mth_seq(N-1, M-1) << endl;
  }
}