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A155509
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Larger of emirps (pairs) with digits 1 and 9 only.
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3
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991, 99119, 191911, 911111, 919111, 999199, 1911911, 1991911, 9111911, 11911111, 19911191, 19919111, 19991911, 99111119, 911111191, 991111111, 991991111, 999199991, 999919919, 1911119911, 1919991191, 1991111911, 1991919191
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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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le19[n_]:=Module[{emrps=Select[FromDigits/@Tuples[{1, 9}, n], !PalindromeQ[ #] && AllTrue[ {#, IntegerReverse[#]}, PrimeQ]&]}, If[IntegerReverse[#]>#, IntegerReverse[ #], {}]&/@emrps/.{}->Nothing]; Flatten[Table[le19[x], {x, 10}]] // Sort (* The program uses the AllTrue function from Mathematica version 10 *) (* Harvey P. Dale, Apr 04 2019 *)
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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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EXTENSIONS
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STATUS
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approved
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