Create an array with repeated numbers
Ruby (recursive), 41 bytes * 0.5 = 20.5
def n(n,i=1);i&gt;n ?[]:n(n,i+1)+[*i..n];end

Or using a lambda (as recommended by histocrat and Ventero): 34 bytes * 0.5 = 17
r=-&gt;n,i=n{i&gt;0?[*i..n]+r[n,i-1]:[]}

(call using r[argument])