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A138358
List of triples of strictly non-palindromic primes without an ordinary prime in between.
2
137, 139, 149, 1433, 1439, 1447, 4337, 4339, 4349, 5297, 5303, 5309, 8287, 8291, 8293, 13049, 13063, 13093, 30293, 30307, 30313, 36007, 36011, 36013, 43391, 43397, 43399
OFFSET
1,1
COMMENTS
Up to 10^9 there are 2992 triples of strictly non-palindromic primes if the quadruples and quintuples are not counted.
For quadruples of this kind, see A138359.
For quintuples of this kind, see A138360.
REFERENCES
Karl Hovekamp, Palindromzahlen in adischen Zahlensystemen, 2004
FORMULA
A small fraction of the primes are strictly non-palindromic. Notice that all strictly non-palindromic numbers >6 are prime! (see: A016038) Triples of these strictly non-palindromic primes, without any normal prime in between, are listed here.
EXAMPLE
Primes:
...
113 is palindromic in base 8
127 is palindromic in base 2 and base 9
131 is palindromic in base 10
137 is strictly non-palindromic
139 is strictly non-palindromic
149 is strictly non-palindromic
151 is palindromic in base 3 and base 10
157 is palindromic in base 7 and base 12
...
So {137, 139, 149} is the first triple of strictly non-palindromic primes.
CROSSREFS
KEYWORD
base,nonn,tabf
AUTHOR
Karl Hovekamp, Mar 16 2008
STATUS
approved