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A226856
Numbers A226770((prime(n))^2-1).
2
1, 1, 1, 3, 1, 1, 3, 1, 3, 5, 1, 46, 1, 5, 66, 1, 1, 3, 3, 3, 10, 3, 1, 1, 172, 1, 1, 398, 5, 132, 255, 1, 336, 41, 1, 3, 615, 1, 462, 918, 283, 1, 1, 1, 453, 1, 11, 713, 1503, 311, 1, 112, 1, 308, 2272, 1, 788, 481, 2301, 1, 2686, 1358, 3, 3, 2651, 3346, 1
OFFSET
1,4
COMMENTS
a(n) = 1 iff (prime(n))^2 + prime(n) - 1 is prime (A053184).
LINKS
MATHEMATICA
Table[(div=Most[Divisors[n+1]]; Length[FixedPoint[Union[Flatten[AppendTo[div, Map[Most[Rest[Divisors[n+#]]]&, #]]]]&, div]]-1), {n, Prime[Range[40]]^2-1}] (* Peter J. C. Moses, Jun 20 2013 *)
CROSSREFS
Sequence in context: A035691 A131781 A082465 * A131327 A355899 A341050
KEYWORD
nonn
AUTHOR
Vladimir Shevelev, Jun 19 2013
EXTENSIONS
More terms from Peter J. C. Moses, Jun 20 2013
STATUS
approved