// Fibonacci n-step number sequences. Nigel Galloway: September 8th., 2022
var nFib:=function(n:array of biginteger): (biginteger,array of biginteger)->(n.First,n[1:].Append(n.Sum).ToArray);
begin
  var fib:=unfold(nFib,1bi,1bi);
  fib.Take(20).Println;
  var tri:=unfold(nFib,fib.Take(3));
  tri.Take(20).Println;
  var tet:=unfold(nFib,tri.Take(4));
  tet.Take(20).Println;
  var pen:=unfold(nFib,tet.Take(5));
  pen.Take(20).Println;
  var hex:=unfold(nFib,pen.Take(6));
  hex.Take(20).Println;
  var hep:=unfold(nFib,hex.Take(7));
  hep.Take(20).Println;
  var oct:=unfold(nFib,hep.Take(8));
  oct.Take(20).Println;
  var non:=unfold(nFib,oct.Take(9));
  non.Take(20).Println;
  var dec:=unfold(nFib,non.Take(10));
  dec.Take(20).Println;
  var luc:=unfold(nFib,2bi,1bi);
  luc.Take(20).Println;
end.