ref: d598a85a44fbac316be27b2dd70546ff44bb4dcf
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)))