Revision as of 22:08, 15 November 2013 (view source) rosettacode>Arbautjc (→‎{{header\|Python}}: loop without division) ← Older edit		Revision as of 18:45, 19 November 2013 (view source) rosettacode>Bearophile (Updated D entry) Newer edit →
Line 419: <lang d>import std.stdio, std.math, std.bigint; bool isPrime(in int p) pure nothrow { if (p < 2 \|\| p % 2 == 0) return p == 2; foreach (immutable i; 3 .. cast(uint)(sqrt(cast(real)p)) + 1) if (p % i == 0) return false; Line 428: } bool isMersennePrime(in int p) /pure /nothrow*/ { if (!~~isPrime(~~p).isPrime) return false; if (p == 2) return true; ~~auto~~immutable mp = (1.BigInt~~(1)~~ << p) - 1; auto s = 4.BigInt~~(4)~~; foreach (immutable _; 3 .. p + 1) s = (s ^^ 2 - 2) % mp; return s == 0; Line 441: void main() { foreach (immutable p; 2 .. 2_300) if ~~(isMersennePrime~~(p).isMersennePrime) { write(" 'M"', p, ' '); stdout.flush(); } }</lang> {{out}} <pre> M2 M3 M5 M7 M13 M17 M19 M31 M61 M89 M107 M127 M521 M607 M1279 M2203 M2281 </pre> With p up to 10_000 it prints: <pre> M2 M3 M5 M7 M13 M17 M19 M31 M61 M89 M107 M127 M521 M607 M1279 M2203 M2281 M3217 M4253 M4423 M9941 </pre> =={{header\|DWScript}}==

Lucas-Lehmer test: Difference between revisions

Lucas-Lehmer test (view source)