$ENTRY Go {
    , <BellNumbers 50>: e.Bell (e.B50)
    , <First 15 e.Bell>: (e.F15) e.Rest
    = <Each (Show) e.F15>
      <Show e.B50>
      <Each (Prout) <BellTriangle 10>>;
}

Show {
    (e.X) = <Prout <Symb e.X>>;
};

BellNumbers {
    s.N, <BellTriangle s.N>: e.Rows = <Each (Head) e.Rows>;
};

BellTriangle {
    s.N = <BellTriangle <Sub s.N 1> ((1))>;
    0 e.T = e.T;
    s.N e.Rs (e.R) = <BellTriangle <Sub s.N 1> e.Rs (e.R) (<BellStep e.R>)>;
};

BellStep {
    e.Row, e.Row: e.X (e.Last) = <Rsum (e.Last) e.Row>;
};

Rsum {
    (Acc e.Acc) = ;
    (Acc e.Acc) (e.N) e.Ns, <Add (e.N) e.Acc>: e.N2 =
        (e.N2) <Rsum (Acc e.N2) e.Ns>;
    e.Ns = <Rsum (Acc 0) e.Ns>;
};

Each {
    (e.F) = ;
    (e.F) (e.X) e.Xs = (<Mu e.F e.X>) <Each (e.F) e.Xs>;
};

Head {
    t.X e.Y = t.X;
};