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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 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

LINKS

Bill McEachen, Table of n, a(n) for n = 1..282

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: A143544 A031346 A087472 * A054348 A239660 A237348

Adjacent sequences:  A172066 A172067 A172068 * A172070 A172071 A172072

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

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Last modified April 24 00:02 EDT 2019. Contains 322404 sequences. (Running on oeis4.)