>>54
hanoi:=method(n,a,b,c,
if(n<1,"",hanoi(n-1,a,c,b)..(a .."->".. b .."\n").. hanoi(n-1,c,b,a)))

Io> hanoi(3,"A","B","C")
==> A->B
A->C
B->C
A->B
C->A
C->B
A->B