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Rosetta: Lucas-Lehmer test

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  Rosetta: Lucas-Lehmer test "WJ" <w_a_x_man@yahoo.com> - 2016-03-29 05:10 +0000
    Re: Rosetta: Lucas-Lehmer test Paul Rubin <no.email@nospam.invalid> - 2016-03-28 23:58 -0700

#46272 — Rosetta: Lucas-Lehmer test

Ocaml (based on the ingenious Pascal solution):

#load "nums.cma" ;;
open Num ;;

let n = ref (Int 1) in
  for exponent = 2 to 2500 do
    let s = ref (Int (if exponent=2 then 0 else 4)) in
      n := pred_num ((succ_num !n) */ Int 2) ;
      for i = 1 to exponent - 2 do
        s := mod_num (!s */ !s -/ Int 2) !n
      done ;
      if !s = Int 0 then
        Printf.printf "%d %!" exponent
  done ;;

 ===>
2 3 5 7 13 17 19 31 61 89 107 127 521 607 1279 2203 2281

Is it wise to try this in ANS Forth?


-- 
[T]he number of Jews killed there was 800,000,000.... [T]he Talmud makes it all
clear by informing us that the blood of the holocausted Jews ran to the sea in
a huge tidal wave that swept boulders in its path and was so deep that it
reached the nostrils of the Romans' horses.
nationalvanguard.org/2014/09/disillusioned-part-1/

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#46275

"WJ" <w_a_x_man@yahoo.com> writes:
> let n = ref (Int 1) in
>   for exponent = 2 to 2500 do
>     let s = ref (Int (if exponent=2 then 0 else 4)) in
>       n := pred_num ((succ_num !n) */ Int 2) ;...

Carl Ludwig Siegel wrote in 1964:

    The whole style of the author contradicts the sense for simplicity
    and honesty which we admire in the works of the masters in number
    theory - Lagrange, Gauss, or on a smaller scale, Hardy, Landau. Just
    now Lang has published another book on algebraic numbers which, in
    my opinion, is still worse than the former one. I see a pig broken
    into a beautiful garden and rooting up all flowers and trees.

He might have been writing about WJ's O'Caml code.

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