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A063086
a(n) = gcd(1 + prime(n+1), 1 + prime(n)).
2
1, 2, 2, 4, 2, 2, 2, 4, 6, 2, 2, 2, 2, 4, 6, 6, 2, 2, 4, 2, 2, 4, 6, 2, 2, 2, 4, 2, 2, 2, 4, 6, 2, 10, 2, 2, 2, 4, 6, 6, 2, 2, 2, 2, 2, 4, 4, 4, 2, 2, 6, 2, 2, 6, 6, 6, 2, 2, 2, 2, 2, 14, 4, 2, 2, 2, 2, 2, 2, 2, 6, 8, 2, 2, 4, 6, 2, 2, 2, 10, 2, 2, 2, 2, 4, 6, 2, 2, 2, 4, 12, 8, 4, 4, 4, 6, 6, 2, 2, 2, 2, 6
OFFSET
1,2
LINKS
EXAMPLE
n=34: gcd(1 + 139, 1 + 149) = 10 = a(34).
MATHEMATICA
GCD[First[#]+1, Last[#]+1]&/@ Partition[Prime[Range[110]], 2, 1] (* Harvey P. Dale, May 02 2012 *)
PROG
(PARI) a(n)={gcd(1 + prime(n+1), 1 + prime(n))} \\ Harry J. Smith, Aug 17 2009
CROSSREFS
Cf. A058263.
Sequence in context: A094818 A114233 A279047 * A077636 A215847 A360460
KEYWORD
easy,nonn
AUTHOR
Labos Elemer, Aug 06 2001
STATUS
approved