A138360 -id:A138360 - cp's OEIS frontend

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

Karl Hovekamp, Mar 16 2008

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.

			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.

Karl Hovekamp, Palindromzahlen in adischen Zahlensystemen, 2004

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.

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

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.

A138359 List of quadruples of strictly non-palindromic primes without an ordinary prime in between them.

Original entry on oeis.org

44449, 44453, 44483, 44491, 120811, 120817, 120823, 120829, 315037, 315047, 315059, 315067, 583069, 583087, 583127, 583139, 617411, 617429, 617447, 617453, 1553423, 1553429, 1553437, 1553467, 1712329, 1712339, 1712353, 1712369

Offset: 1

Karl Hovekamp, Mar 16 2008

For triples of this kind, see A138358.

For quintuples of this kind, see A138360.

			Primes:
...
44417 palindromic in bases 50, 106, 135 and 141
44449 strictly non-palindromic
44453 strictly non-palindromic
44483 strictly non-palindromic
44491 strictly non-palindromic
44497 palindromic in base 67 and base 206
...
So {44449, 44453, 44483, 44491} is the first quadruple of strictly non-palindromic primes.

Karl Hovekamp, Palindromzahlen in adischen Zahlensystemen, 2004

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.

Cf. A138358, A138360, A138329, A016038, A047811, A016038.

cp's OEIS Frontend

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

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