Data commit

Task/Repunit-primes/ALGOL-68/repunit-primes.alg

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+BEGIN # find repunit (all digits are 1 ) primes in various bases #
+    INT max base           = 16;
+    INT max repunit digits = 1000;
+    PR precision 3000 PR        # set precision of LONG LONG INT #
+    # 16^1000 has ~1200 digits but the primality test needs more #
+    PR read "primes.incl.a68" PR       # include prime utilities #
+    []BOOL prime = PRIMESIEVE max repunit digits;
+    FOR base FROM 2 TO max base DO
+        LONG LONG INT repunit := 1;
+        print( ( whole( base, -2 ), ":" ) );
+        FOR digits TO max repunit digits DO
+            IF prime[ digits ] THEN
+                IF is probably prime( repunit ) THEN
+                    # found a prime repunit in the current base #
+                    print( ( " ", whole( digits, 0 ) ) )
+                FI
+            FI;
+            repunit *:= base +:= 1
+        OD;
+        print( ( newline ) )
+    OD
+END