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A069467
Twin primes belonging to packs of three or more twin pairs.
1
3, 5, 7, 11, 13, 17, 19, 179, 181, 191, 193, 197, 199, 809, 811, 821, 823, 827, 829, 3359, 3361, 3371, 3373, 3389, 3391, 4217, 4219, 4229, 4231, 4241, 4243, 6761, 6763, 6779, 6781, 6791, 6793, 9419, 9421, 9431, 9433, 9437, 9439, 9461, 9463, 18041
OFFSET
1,1
EXAMPLE
A twin pack of primes contains 2 or more pairs of twin primes, between which pairs there are no other primes. 179, 181, 191, 193, 197, 199 are in the sequence because they are consecutive primes which belong to more than 2 twin pairs. 137, 139, 149, 151 are not because they belong to a pack of only 2 pairs.
MATHEMATICA
lst={3}; d=2; Do[p0=Prime[n+0]; p1=Prime[n+1]; p2=Prime[n+2]; p3=Prime[n+3]; p4=Prime[n+4]; p5=Prime[n+5]; d1=p1-p0; d2=p3-p2; d3=p5-p4; If[d1==d&&d2==d&&d3==d, AppendTo[lst, p0]; AppendTo[lst, p1]; AppendTo[lst, p2]; AppendTo[lst, p3]; AppendTo[lst, p4]; AppendTo[lst, p5]], {n, 10^4}]; Union[lst] (* Vladimir Joseph Stephan Orlovsky, Aug 08 2008 *)
CROSSREFS
Sequence in context: A096880 A069458 A062280 * A309739 A249876 A096169
KEYWORD
nonn
AUTHOR
Neil Fernandez, Mar 24 2002
STATUS
approved