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A176820
Number of primes between 3*A171821(2n-1) and 3*A171821(2n).
0
1, 2, 1, 1, 1, 1, 2, 0, 1, 0, 0, 1, 1, 1, 1, 1, 1, 2, 0, 1, 0, 1, 1, 0, 1, 1, 1, 0, 0, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 1, 0, 1, 0, 1, 1, 1, 1, 0, 1, 1, 0, 1, 0, 0, 0, 0, 2, 0, 0, 1, 1, 1, 1, 1, 0, 1, 0, 1, 0, 1, 0, 0, 0, 0, 1, 1, 0, 0, 2, 0, 0, 0, 0, 1, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 1, 1, 0
OFFSET
1,2
COMMENTS
Where 2 together with twin primes in A171821.
EXAMPLE
a(1)=1 because 7 is between 3*A171821(2*1-1)=6 and 3*A171821(2*1)=9.
a(2)=2 because 17 and 19 are between 3*A171821(2*2-1)=15 and 3*A171821(2*2)=21.
CROSSREFS
Sequence in context: A326698 A299432 A252911 * A343776 A328384 A016024
KEYWORD
nonn
AUTHOR
EXTENSIONS
a(42) corrected by R. J. Mathar, May 06 2010
STATUS
approved