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A158277
The lesser of twin prime pairs with each prime in a different century.
10
599, 2999, 3299, 4799, 5099, 6299, 8999, 10499, 11699, 21599, 25799, 26699, 29399, 33599, 34499, 36899, 37199, 42899, 44699, 47699, 49199, 56099, 57899, 60899, 63599, 65099, 65699, 70199, 74099, 81899, 83399, 85199, 88799, 92399, 97499, 100799, 101999, 102299
OFFSET
1,1
COMMENTS
The sequence is conjecturally infinite; note that those ending in 999 straddle millenia: A158861.
Since any prime greater than 3 is congruent to 1 or 5 modulo 6, a(n)+1 is divisible by 300 (see A001359). - Hartmut F. W. Hoft, May 18 2017
LINKS
MATHEMATICA
Select[Range[100, 110000, 100], AllTrue[#+{1, -1}, PrimeQ]&]-1 (* The program uses the AllTrue function from Mathematica version 10 *) (* Harvey P. Dale, Oct 21 2016 *)
a158277[n_] := Map[Last, Select[Map[{NextPrime[#, 1], NextPrime[#, -1]}&, Range[100, n, 100]], First[#]-Last[#]==2&]]
a158277[105000] (* data *) (* Hartmut F. W. Hoft, May 18 2017 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Ki Punches, Mar 15 2009
EXTENSIONS
Corrected by Ray Chandler and R. J. Mathar, Apr 03 2009
STATUS
approved