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A073805 Numbers k such that 1 + k*R(k) is prime, where R(k) is the reverse of k. 1

%I

%S 1,2,4,6,10,16,18,20,24,25,26,28,36,42,50,52,58,61,62,63,66,68,70,80,

%T 81,82,85,86,90,100,108,112,116,120,132,136,138,140,152,162,170,190,

%U 198,200,204,205,209,210,211,213,214,219,223,224,228,231,234,236,238

%N Numbers k such that 1 + k*R(k) is prime, where R(k) is the reverse of k.

%e 16 is a term because 16*61 + 1 = 977 is prime.

%t Select[Range[250],PrimeQ[# IntegerReverse[#]+1]&] (* Requires Mathematica version 10 or later *) (* _Harvey P. Dale_, Oct 05 2017 *)

%K easy,base,nonn

%O 1,2

%A _Shyam Sunder Gupta_, Aug 23 2002

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Last modified February 4 11:10 EST 2023. Contains 360055 sequences. (Running on oeis4.)