A098422 Primes occurring in exactly two prime triples (p,q,r) with p

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

Author

Reinhard Zumkeller, Sep 07 2004

Keywords

• nonn

Comments

A098418(a(n)) = 2; subsequence of A098420.

Links

• Eric Weisstein's World of Mathematics, Prime Triplet

Crossrefs

Cf. A098419, A098421, A098423.

Programs

Mathematica

Select[Tally[Flatten[Select[Partition[Prime[Range[800]],3,1],#[[3]]- #[[1]] == 6&]]],#[[2]]==2&][[All,1]] (* Harvey P. Dale, Jun 01 2019 *)