Data update

Task/Circular-primes/REXX/circular-primes-2.rexx

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+include Settings
+
+say version; say 'Circular primes'; say
+call First19
+call Next3
+call HigherReps
+exit
+
+First19:
+procedure expose glob. prim.
+call Time('r')
+numeric digits 10
+say 'First 19 circular primes:'
+p = Primes(200000)
+do i = 1 to p
+   a = prim.prime.i
+   if Verify(a,'024568','m') > 0 then
+      iterate i
+   b = a; l = Length(b)
+   do l-1
+      b = Right(b,l-1)||Left(b,1)
+      if b < a then
+         iterate i
+      if \ IsPrime(b) then
+         iterate i
+   end
+   call Charout ,a' '
+end
+say
+say Format(Time('e'),,3) 'seconds'
+say
+return
+
+Next3:
+procedure expose glob.
+call Time('r')
+numeric digits 320
+say 'Next 3 circular primes:'
+do i = 7 to 320
+   r = Repunit(i)
+   if IsPrime(r) then
+      call charout ,'R('i') '
+end
+say
+say Format(Time('e'),,3) 'seconds'
+say
+return
+
+HigherReps:
+procedure expose glob.
+call Time('r')
+numeric digits 1040
+say 'Primality of R(1031):'
+if IsPrime(Repunit(1031)) then
+   say 'R(1031) is probable prime'
+else
+   say 'R(1031) is composite'
+say Format(Time('e'),,3) 'seconds'
+say
+return
+
+Repunit:
+/* Repeat 1's function */
+procedure expose glob.
+arg x
+/* Formula */
+return Copies('1',x)
+
+include Numbers
+include Functions
+include Abend