A255480 a(n) = gcd(b(n),b(n-2)), where b(n) = A255582(n).

1, 2, 3, 4, 3, 2, 3, 5, 2, 5, 7, 3, 7, 2, 3, 4, 3, 4, 11, 2, 11, 13, 2, 13, 4, 3, 2, 5, 17, 5, 17, 5, 3, 2, 6, 19, 4, 19, 2, 3, 23, 3, 23, 2, 3, 2, 2, 4, 29, 7, 29, 7, 3, 7, 2, 11, 31, 5, 31, 5, 3, 2, 2, 4, 37, 4, 37, 3, 3, 5, 3, 4, 9, 2, 6, 41, 2, 41, 43, 3, 43, 8, 3, 4, 17

Offset: 3

Author

N. J. A. Sloane, Feb 28 2015

Keywords

• nonn

Links

• Ray Chandler, Table of n, a(n) for n = 3..10002

Crossrefs

Cf. A255582, A255481, A255102.

Cf. A251102.

Programs

Haskell

a255480 n = a255480_list !! (n-1)
a255480_list = zipWith gcd a255582_list $ drop 2 a255582_list
-- Reinhard Zumkeller, Mar 10 2015