login
A134702
Initial prime, greater than 5, of a prime chain of length n under the iteration x->2x-5.
1
7, 11, 11, 11, 11, 11, 11, 11, 29614931, 29614931, 1172182334669, 67667595358511, 124204021800149
OFFSET
1,1
EXAMPLE
a(3) = 11 because 11 11*2-5=17 and 17*2-5=29 are primes.
CROSSREFS
Cf. A084954.
Sequence in context: A133891 A071631 A054510 * A053674 A205679 A166980
KEYWORD
nonn,more
AUTHOR
Don Reble, Nov 07 2007
STATUS
approved