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A098422
Primes occurring in exactly two prime triples (p,q,r) with p<q<r=p+6.
3
7, 19, 41, 43, 101, 109, 193, 197, 227, 229, 311, 313, 461, 463, 823, 827, 857, 859, 881, 883, 1091, 1093, 1301, 1303, 1427, 1429, 1483, 1489, 1871, 1877, 1997, 1999, 2083, 2087, 2687, 2689, 3253, 3257, 3461, 3467, 4517, 4519, 4787, 4789, 5231, 5233, 5651
OFFSET
1,1
COMMENTS
A098418(a(n)) = 2; subsequence of A098420.
LINKS
Eric Weisstein's World of Mathematics, Prime Triplet
MATHEMATICA
Select[Tally[Flatten[Select[Partition[Prime[Range[800]], 3, 1], #[[3]]- #[[1]] == 6&]]], #[[2]]==2&][[All, 1]] (* Harvey P. Dale, Jun 01 2019 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Reinhard Zumkeller, Sep 07 2004
STATUS
approved