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 A241212 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. 1
 23, 67, 89, 1021, 1223, 1627, 3041, 4051, 4253, 4657, 5869, 7283, 7687, 8293, 106217, 110221, 112223, 128239, 130241, 136247, 158269, 172283, 178289, 188299, 208319, 226337, 230341, 250361, 272383, 286397, 320431, 322433, 326437, 328439, 338449, 340451 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Robert Israel, Table of n, a(n) for n = 1..10000 EXAMPLE E.g., for 2 digit primes: (3, 7, 9) = (2, 6, 8) + 1. MAPLE N:= 1000; # to get the first N entries A241212[1]:= 23: A241212[2]:= 67: A241212[3]:= 89: count:= 3: for n from 2 while count < N do   for x1 from 10^(n-1) to 9*10^(n-1)-2 by 2 while count < N do     L:= convert(x1, base, 10);     if has(L, 9) then next fi;     x:= 10^n*x1 + x1 + (10^n - 1)/9;     if isprime(x) then       count:= count+1;       A241212[count]:= x     fi;   od od: # Robert Israel, Apr 18 2014 CROSSREFS Sequence in context: A141849 A125873 A059241 * A052087 A030458 A053559 Adjacent sequences:  A241209 A241210 A241211 * A241213 A241214 A241215 KEYWORD nonn,base AUTHOR Zak Seidov, Apr 17 2014 EXTENSIONS Incorrect cross-reference deleted by Robert Israel, Apr 18 2014 STATUS approved

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Last modified January 16 06:48 EST 2021. Contains 340204 sequences. (Running on oeis4.)