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A237283
Primes p with prime(prime(p)) + 2 also prime.
3
2, 3, 7, 13, 23, 29, 59, 71, 103, 193, 257, 271, 281, 311, 317, 389, 433, 439, 463, 569, 577, 619, 673, 683, 691, 797, 811, 857, 859, 887, 1031, 1069, 1109, 1129, 1153, 1229, 1307, 1597, 1613, 1867, 1949, 1951, 2069, 2297, 2477, 2551, 2621, 2657, 2699, 2753
OFFSET
1,1
COMMENTS
This sequence is interesting because of the conjecture in A237253.
A236481, A236482 and A236484 are subsequences of the sequence.
EXAMPLE
a(1) = 2 since 2 and prime(prime(2)) + 2 = prime(3) + 2 = 7 are both prime.
MATHEMATICA
n=0; Do[If[PrimeQ[Prime[Prime[Prime[k]]]+2], n=n+1; Print[n, " ", Prime[k]]], {k, 1, 1000}]
Select[Prime[Range[500]], PrimeQ[Prime[Prime[#]]+2]&] (* Harvey P. Dale, May 30 2018 *)
KEYWORD
nonn
AUTHOR
Zhi-Wei Sun, Feb 05 2014
STATUS
approved