fcn binomial(n,k){ (1).reduce(k,fcn(p,i,n){ p*(n-i+1)/i },1,n) }
fcn pascal_upp(n){ [[(i,j); n; n; '{ binomial(j,i) }]]:toMatrix(_) } // [[..]] is list comprehension
fcn pascal_low(n){ [[(i,j); n; n; binomial]]:toMatrix(_) }
fcn pascal_sym(n){ [[(i,j); n; n; '{ binomial(i+j,i) }]]:toMatrix(_) }
fcn toMatrix(ns){ // turn a string of numbers into a square matrix (list of lists)
   cols:=ns.len().toFloat().sqrt().toInt();
   ns.pump(List,T(Void.Read,cols-1),List.create)
}