| Hi and welcome, e.g. ( ~collatz = { arg start, limit = 1000; var num = start, col = [start], count = 1; while { (num != 1) and: { count <= limit } }{ num = num.even.if { num.div(2) }{ num * 3 + 1 }; col = col.add(num); count = count + 1; }; col } ) ~collatz.(23) -> [ 23, 70, 35, 106, 53, 160, 80, 40, 20, 10, 5, 16, 8, 4, 2, 1 ] Greetings Daniel ----------------------------- http://daniel-mayer.at ----------------------------- |