

A134951


Mountain primes.


16



131, 151, 181, 191, 1231, 1291, 1321, 1361, 1381, 1451, 1471, 1481, 1531, 1571, 1621, 1721, 1741, 1831, 1861, 1871, 1931, 1951, 12391, 12421, 12451, 12491, 12541, 12641, 12671, 12721, 12781, 12791, 12821, 12841, 12941, 13421, 13451, 13591, 13681
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OFFSET

1,1


COMMENTS

Mountain numbers that are prime numbers.
This sequence has 2620 terms. The largest is 134567897654321. [From Jud McCranie, Feb 23 2009, Feb 24 2009]


REFERENCES

Chris K. Caldwell and G. L. Honaker, Jr; Prime Curios!, The Dictionary of Prime Number Trivia, CreateSpace (2009), p. 69, 216, 217.


LINKS

Giovanni Resta, Table of n, a(n) for n = 1..2620 (full sequence)
G. L. Honaker, Jr. and Chris K. Caldwell, Prime Curios! 2620


FORMULA

A000040 INTERSECT A134941.
A178333(a(n))*A010051(a(n)) = 1. [From Reinhard Zumkeller, May 25 2010]


EXAMPLE

The Anumber of this sequence (A134951) is a mountain prime because 134951 is a mountain number and it is also a prime number.
. . . 9 . .
. . . . . .
. . . . . .
. . . . . .
. . . . 5 .
. . 4 . . .
. 3 . . . .
. . . . . .
1 . . . . 1


CROSSREFS

Cf. A000040, A134941.
Sequence in context: A045164 A167845 A273049 * A173071 A164294 A155924
Adjacent sequences: A134948 A134949 A134950 * A134952 A134953 A134954


KEYWORD

fini,full,nonn,base


AUTHOR

Omar E. Pol, Nov 25 2007


EXTENSIONS

Edited by Omar E. Pol, Feb 26 2009
More terms from Max Alekseyev, Feb 06 2010
Minor edit and reference added by Omar E. Pol, Mar 25 2011


STATUS

approved



