ref: 21dd64045484411ef9c9f218c1490fd02c02b3fd
dir: /femtolisp/tests/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)))