エラトステネスの篩

prime.scm

(define (prime n)
  (let loop ((lst (iota (- n 1) 2))(result '()))
    (let ((solve (cons (car lst) result)))
      (if (< (last lst) (* (car solve) (car solve)))
        (append (reverse result) lst)
        (loop (remove (^(x)(zero? (remainder x (car lst)))) lst) solve)))))