A138358 List of triples of strictly non-palindromic primes without an ordinary prime in between.

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

Links

Table of n, a(n) for n=1..27.

K. Hovekamp, Palindromic numbers in different bases.

K. Hovekamp, Strictly non-palindromic prime 5-tuple, quadruple and triple up to 1 billion

Wikipedia, Strictly non-palindromic numbers.

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

Cf. A138359, A138360, A138329, A016038, A047811, A016038.

Sequence in context: A259680 A082726 A189998 * A138329 A066477 A139647

Adjacent sequences: A138355 A138356 A138357 * A138359 A138360 A138361

Keyword

base,nonn,tabf

Author

Karl Hovekamp, Mar 16 2008

Status

approved