A263241 Lesser of emirp pairs that are merely reversals of their end digits.
13, 17, 37, 79, 107, 113, 149, 157, 167, 179, 199, 337, 347, 359, 389, 709, 739, 769, 1009, 1223, 1229, 1559, 1669, 3889, 7229, 10007, 10009, 10909, 11717, 11719, 12227, 12323, 12829, 13337, 13933, 14143, 14447, 14449, 14549, 14843, 14947, 15053, 16063, 16267, 16567, 16763
Offset: 1
Programs
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Mathematica
Select[Range[20000], And @@ PrimeQ[{#, IntegerReverse[#]}] && ! PalindromeQ[#] && First[(d = IntegerDigits[#])] < Last[d] && PalindromeQ[Most@ Rest@ IntegerDigits[#]] &] (* Amiram Eldar, Oct 16 2021 *) -
PARI
isok(p) = my(dp=digits(p), dr=Vecrev(dp), r=fromdigits(dr)); if (isprime(r) && (r>p) && isprime(p), sum(i=2, #dp-1, dp[i]==dr[i]) == #dp-2); \\ Michel Marcus, Oct 16 2021
Extensions
Missing 179 added by Zak Seidov, Oct 15 2021
Comments