ref: f2a727baa2b48a5a9ac99de0bc437280e51d02b4
dir: /test/pisum.lsp/
(define (pisum)
(dotimes (j 500)
((label sumloop
(lambda (i sum)
(if (> i 10000)
sum
(sumloop (+ i 1) (+ sum (/ (* i i)))))))
1.0 0.0)))