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Numbers n whose 10's complement is prime, i.e., 10^k-n, where k is the number of digits of n, is prime.
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%I #10 Apr 28 2019 18:27:58

%S 3,5,7,8,11,17,21,27,29,33,39,41,47,53,57,59,63,69,71,77,81,83,87,89,

%T 93,95,97,98,113,117,119,123,137,141,143,147,161,171,173,177,179,189,

%U 191,203,213,227,231,239,243,249,257,261,267,273,281,291,299

%N Numbers n whose 10's complement is prime, i.e., 10^k-n, where k is the number of digits of n, is prime.

%C A068811 is a subset.

%H Jayanta Basu, <a href="/A228075/b228075.txt">Table of n, a(n) for n = 1..1000</a>

%e 8 is a term since 10^1 - 8 = 2 is a prime.

%e Similarly, 39 is a term as 10^2 - 39 = 61 is prime.

%t Select[Range[300], PrimeQ[10^(IntegerLength[#]) - #] &]

%Y Cf. A068811.

%K nonn,base

%O 1,1

%A _Jayanta Basu_, Aug 09 2013