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%I #19 Apr 18 2014 02:36:54
%S 23,67,89,1021,1223,1627,3041,4051,4253,4657,5869,7283,7687,8293,
%T 106217,110221,112223,128239,130241,136247,158269,172283,178289,
%U 188299,208319,226337,230341,250361,272383,286397,320431,322433,326437,328439,338449,340451
%N Primes p with an even number of digits such that each digit in the second half of p is larger by 1 than the corresponding digit in the first half.
%H Robert Israel, <a href="/A241212/b241212.txt">Table of n, a(n) for n = 1..10000</a>
%e E.g., for 2 digit primes: (3, 7, 9) = (2, 6, 8) + 1.
%p N:= 1000; # to get the first N entries
%p A241212[1]:= 23:
%p A241212[2]:= 67:
%p A241212[3]:= 89:
%p count:= 3:
%p for n from 2 while count < N do
%p for x1 from 10^(n-1) to 9*10^(n-1)-2 by 2 while count < N do
%p L:= convert(x1,base,10);
%p if has(L,9) then next fi;
%p x:= 10^n*x1 + x1 + (10^n - 1)/9;
%p if isprime(x) then
%p count:= count+1;
%p A241212[count]:= x
%p fi;
%p od
%p od: # _Robert Israel_, Apr 18 2014
%K nonn,base
%O 1,1
%A _Zak Seidov_, Apr 17 2014
%E Incorrect cross-reference deleted by _Robert Israel_, Apr 18 2014
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