A155514
Larger of emirps (pairs) with digits 0 and 1 only.
Original entry on oeis.org
10111001, 111001001, 1010110001, 1011000101, 1101001001, 1111100101, 10100101001, 11000000101, 11010011101, 11100000101, 100111101001, 101010000001, 101010111001, 110000000101, 110011010101, 110101011001
Offset: 1
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emrpQ[n_]:=Module[{idn=IntegerDigits[n],ridn},ridn=Reverse[idn]; idn!=ridn &&PrimeQ[n]&&PrimeQ[FromDigits[ridn]]]; lrgr[n_]:=If[nHarvey P. Dale, Oct 01 2012 *)
A155513
Lesser of emirps (pairs) with digits 0 and 1 only.
Original entry on oeis.org
10011101, 100100111, 1000110101, 1001001011, 1010001101, 1010011111, 10010100101, 10100000011, 10100000111, 10111001011, 100000010101, 100000011011, 100101110111, 100101111001, 100110101011, 100110101111
Offset: 1
A209620
Emirps that become their own reversals when rotated through 180 degrees (including on calculator display).
Original entry on oeis.org
1021, 1151, 1181, 1201, 1511, 1811, 10151, 11551, 15101, 15511, 100511, 101281, 102181, 102551, 105211, 105251, 108881, 110051, 110221, 110281, 110881, 111211, 111821, 112111, 112181, 112501, 115001, 115021, 118081, 120121, 120511, 121021, 121151, 122011
Offset: 1
1181 of this sequence, for instance, belongs to the emirp pair (1181, 1811), where each member is a 180-degree rotation of the other; similarly for the term 112501 of this sequence, that belongs to the emirp pair (105211, 112501) and which, displayed on a calculator and turned upside-down, becomes its own reversal.
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t1 = {0, 1, 2, 5, 8}; okQ[n_] := Module[{d = IntegerDigits[n], r}, r = Reverse[d]; r != d && Complement[d, t1] == {} && PrimeQ[FromDigits[r]]]; Select[Prime[Range[100000]], okQ] (* T. D. Noe, Apr 24 2012 *)
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