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A251102
a(n) = gcd(A098550(n+2), A098550(n)).
4
1, 2, 3, 4, 3, 2, 5, 2, 5, 6, 5, 4, 7, 2, 7, 10, 3, 2, 3, 11, 13, 11, 13, 3, 2, 3, 4, 17, 2, 17, 6, 5, 2, 5, 2, 13, 6, 7, 2, 7, 19, 21, 19, 2, 19, 4, 3, 10, 23, 2, 23, 4, 5, 2, 3, 2, 3, 2, 29, 31, 29, 31, 2, 3, 4, 11, 2, 7, 6, 7, 6, 7, 6, 7, 2, 35, 37, 35
OFFSET
1,2
COMMENTS
For n > 1: a(n) > 1, by definition of A098550;
gcd(a(n+1), a(n)) = 1;
gcd(a(n), A098550(n)) = a(n).
LINKS
PROG
(Haskell)
a251102 n = a251102_list !! (n-1)
a251102_list = zipWith gcd (drop 2 a098550_list) a098550_list
CROSSREFS
Sequence in context: A309859 A341861 A303597 * A111880 A348599 A306461
KEYWORD
nonn
AUTHOR
Reinhard Zumkeller, Nov 30 2014
STATUS
approved