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A234901
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Primes which remain prime when the digits are rotated once to the right.
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2
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2, 3, 5, 7, 11, 13, 17, 31, 37, 71, 73, 79, 97, 113, 131, 173, 197, 199, 271, 277, 311, 313, 337, 373, 379, 397, 419, 479, 491, 571, 577, 593, 617, 631, 673, 719, 733, 811, 839, 877, 911, 919, 971, 977, 991, 1031, 1039, 1091, 1093, 1097, 1171, 1193, 1213
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OFFSET
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1,1
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LINKS
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EXAMPLE
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The prime 1097 is in the list because 7109 is also prime.
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MATHEMATICA
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Select[Prime[Range[200]], PrimeQ[FromDigits[RotateRight[IntegerDigits[#]]]]&] (* Harvey P. Dale, May 05 2022 *)
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PROG
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(PARI) rotr(a) = if(a<10, a, eval(Str(a%10, a\10)))
s=[]; forprime(n=2, 2000, if(isprime(rotr(n)), s=concat(s, n))); s
(Magma) r:=func<i | Seqint(Intseq(Floor(i/10)) cat Intseq(Intseq(i)[1]))>; [p: p in PrimesUpTo(1300) | IsPrime(r(p))]; // Bruno Berselli, Jul 04 2014
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CROSSREFS
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KEYWORD
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nonn,base
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AUTHOR
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STATUS
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approved
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