"^^^"(a, n) := block(
   [p: 1],
   while n > 0 do (
      if oddp(n) then p: p * a,
      a: a * a,
      n: quotient(n, 2)
   ),
   p
)$

infix("^^^")$

2 ^^^ 10;
1024

2.5 ^^^ 10;
9536.7431640625