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Mountain primes.
16

%I #25 Apr 03 2023 10:36:11

%S 131,151,181,191,1231,1291,1321,1361,1381,1451,1471,1481,1531,1571,

%T 1621,1721,1741,1831,1861,1871,1931,1951,12391,12421,12451,12491,

%U 12541,12641,12671,12721,12781,12791,12821,12841,12941,13421,13451,13591,13681

%N Mountain primes.

%C Mountain numbers that are prime numbers.

%C This sequence has 2620 terms. The largest is 134567897654321. - _Jud McCranie_, Feb 23 2009, Feb 24 2009

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

%H Giovanni Resta, <a href="/A134951/b134951.txt">Table of n, a(n) for n = 1..2620</a> (full sequence)

%H G. L. Honaker, Jr. and Chris K. Caldwell, <a href="https://t5k.org/curios/page.php?number_id=8409">Prime Curios! 2620</a>

%F A000040 INTERSECT A134941.

%F A178333(a(n))*A010051(a(n)) = 1. - _Reinhard Zumkeller_, May 25 2010

%e The A-number of this sequence (A134951) is a mountain prime because 134951 is a mountain number and it is also a prime number.

%e . . . 9 . .

%e . . . . . .

%e . . . . . .

%e . . . . . .

%e . . . . 5 .

%e . . 4 . . .

%e . 3 . . . .

%e . . . . . .

%e 1 . . . . 1

%Y Cf. A000040, A134941.

%K fini,full,nonn,base

%O 1,1

%A _Omar E. Pol_, Nov 25 2007

%E Edited by _Omar E. Pol_, Feb 26 2009

%E More terms from _Max Alekseyev_, Feb 06 2010

%E Minor edit and reference added by _Omar E. Pol_, Mar 25 2011