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A167513
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Primes p such that (p reversed)-4 is also prime
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2
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7, 11, 17, 53, 71, 101, 113, 131, 137, 149, 167, 173, 179, 197, 311, 317, 347, 353, 383, 557, 599, 701, 761, 773, 1031, 1049, 1061, 1109, 1163, 1193, 1223, 1277, 1289, 1307, 1319, 1361, 1373, 1427, 1439, 1553, 1559, 1571, 1583, 1607, 1619, 1709, 1787, 1847
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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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71->17-4=13; 53->35-4=31; 137->731-4=727.
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MATHEMATICA
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Select[Prime[Range[2, 300]], PrimeQ[FromDigits[Reverse[IntegerDigits[#]]] - 4]&] (* Vincenzo Librandi, Apr 15 2013 *)
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PROG
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(Magma) [p: p in PrimesInInterval(5, 2000) | IsPrime(q-4) where q is Seqint(Reverse(Intseq(p)))]; // Bruno Berselli, Apr 15 2013
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CROSSREFS
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KEYWORD
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nonn,base,easy
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AUTHOR
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EXTENSIONS
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Corrected (379 replaced by 383) and extended by R. J. Mathar, Nov 30 2009
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STATUS
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approved
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