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A263242
Larger of emirp pairs that are merely reversals of their end digits.
3
31, 71, 73, 97, 311, 701, 733, 743, 751, 761, 907, 937, 941, 953, 967, 971, 983, 991, 3221, 9001, 9221, 9227, 9551, 9661, 9883, 32321, 33931, 34141, 34841, 35051, 36061, 36761, 37571, 39791, 70001, 71711, 72221, 73331, 74143, 74441, 74843, 74941, 75253, 76261, 76463, 76561
OFFSET
1,1
COMMENTS
The first digit is always larger than the last digit.
LINKS
MATHEMATICA
epQ[n_]:=Module[{idn=IntegerDigits[n], mid}, mid=Rest[Most[idn]]; PrimeQ[ IntegerReverse[n]]&&mid==Reverse[mid]&&idn[[1]]>idn[[-1]]]; Select[ Prime[Range[6, 8000]], epQ] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, Oct 10 2016 *)
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Lekraj Beedassy, Oct 13 2015
EXTENSIONS
Corrected by Harvey P. Dale, Oct 10 2016
STATUS
approved