

A236482


Primes p with p + 2, prime(p) + 2, prime(prime(p)) + 2 and prime(prime(prime(p))) + 2 all prime.


4



41609, 1119047, 1928621, 2348579, 2371709, 3406727, 4098569, 4204817, 4438997, 5561819, 6161159, 6293297, 8236439, 8736701, 8890667, 8951387, 9231329, 9390077, 10492457, 10619897, 11255729, 11514719, 11769479, 11920661, 12316697
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OFFSET

1,1


COMMENTS

According to the general conjecture in A236481, this sequence should have infinitely many terms.


LINKS

ZhiWei Sun, Table of n, a(n) for n = 1..100


EXAMPLE

a(1) = 41609 with 41609, 41609 + 2 = 41611, prime(41609) + 2 = 500909 + 2 = 500911, prime(500909) + 2 = 7382957 + 2 = 7382959 and prime(7382957) + 2 = 130090109 + 2 = 130090111 all prime.


MATHEMATICA

p[n_]:=p[n]=PrimeQ[n+2]&&PrimeQ[Prime[n]+2]&&PrimeQ[Prime[Prime[n]]+2]&&PrimeQ[Prime[Prime[Prime[n]]]+2]
n=0; Do[If[p[Prime[m]], n=n+1; Print[n, " ", Prime[m]]], {m, 1, 10^6}]


CROSSREFS

Cf. A000040, A001359, A006512, A236457, A236458, A236467, A236480, A236481, A236484.
Sequence in context: A165114 A002879 A207049 * A163392 A262801 A253681
Adjacent sequences: A236479 A236480 A236481 * A236483 A236484 A236485


KEYWORD

nonn


AUTHOR

ZhiWei Sun, Jan 26 2014


STATUS

approved



