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A172069
The number of primes adjacent to A129912(n): 0, 1 or 2.
1
1, 1, 2, 2, 2, 2, 2, 1, 1, 2, 1, 2, 1, 1, 2, 1, 1, 0, 1, 1, 0, 0, 0, 1, 2, 0, 2, 1, 0, 1, 0, 1, 1, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 1, 0, 1, 1, 0, 1, 0, 0, 1, 1, 1, 0, 1, 1, 0, 0, 0, 1, 1, 1, 0, 0, 0, 2, 1, 0, 1, 0, 1, 0, 0, 0, 1, 1, 1, 0, 1, 0, 1, 0, 0, 1, 0, 0, 0, 1, 0, 1, 1, 0, 1, 1, 1, 0, 0, 0, 1, 1, 2, 0, 0
OFFSET
1,3
LINKS
EXAMPLE
Both 415799 and 415801 are prime, so the entry at 415800 (n=27) is a 2 (twin primes).
Neither 27719 nor 27721 are prime, so the entry at 27720 (n=18) is a 0.
CROSSREFS
Cf. A129912.
Sequence in context: A031346 A335808 A087472 * A054348 A239660 A237348
KEYWORD
easy,nonn
AUTHOR
Bill McEachen, Jan 24 2010
EXTENSIONS
Offset corrected and sequence extended by R. J. Mathar, Feb 19 2010
a(1) added by T. D. Noe, Nov 11 2013
STATUS
approved