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A174262
Primes of the form 21^(2^n) + 2.
0
23, 443, 194483
OFFSET
1,1
COMMENTS
a(n) is congruent 3 mod 4.
The next term (if it exists) corresponds to some n>23, so it has more than 11 million digits. [R. J. Mathar, Aug 23 2010]
CROSSREFS
Sequence in context: A203147 A158453 A291128 * A174425 A076068 A062273
KEYWORD
nonn,bref
AUTHOR
Giovanni Teofilatto, Mar 14 2010
EXTENSIONS
Entries checked. - R. J. Mathar, Aug 23 2010
STATUS
approved