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A109309
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Larger emirps (primes whose digit reversal is a lesser prime).
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8
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31, 71, 73, 97, 311, 701, 733, 743, 751, 761, 907, 937, 941, 953, 967, 971, 983, 991, 1201, 1301, 1321, 1511, 1601, 1741, 1811, 1831, 1901, 3011, 3121, 3191, 3203, 3221, 3251, 3271, 3301, 3371, 3391, 3433, 3511, 3541, 3571, 3613, 3643, 3733, 3803, 3821
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OFFSET
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1,1
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LINKS
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MATHEMATICA
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dr[n_]:=FromDigits[Reverse[IntegerDigits[n]]]; Select[Prime[Range[1000]], PrimeQ[dr[ # ]]&&dr[ # ]<#&]
Select[Prime[Range[600]], PrimeQ[IntegerReverse[#]]&&#>IntegerReverse[#]&] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, Jul 23 2020 *)
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CROSSREFS
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Cf. A006567 Emirps (primes whose digit reversal is a different prime), A109308 Lesser emirps (primes whose digit reversal is a larger prime).
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KEYWORD
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base,nonn
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AUTHOR
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STATUS
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approved
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