A338440 a(n) is the greatest common divisor of A338338(n), A338338(n+1) and A338338(n+2).

1, 2, 1, 3, 1, 1, 5, 2, 1, 1, 7, 2, 1, 3, 5, 2, 1, 1, 11, 2, 1, 3, 7, 2, 1, 3, 1, 11, 5, 2, 1, 13, 1, 3, 4, 1, 1, 17, 2, 1, 19, 1, 3, 5, 2, 7, 3, 1, 17, 5, 2, 1, 23, 1, 3, 2, 11, 1, 7, 5, 3, 1, 2, 13, 3, 1, 1, 5, 13, 2, 1, 29, 1, 3, 10, 1, 1, 31, 2, 1, 1, 37

Offset

1,2

Comments

No prime factor of a(n) divides A338338(n+3).

Links

Rémy Sigrist, Table of n, a(n) for n = 1..10000

Rémy Sigrist, C program for A338440

Formula

gcd(a(n), A338338(n+3)) = 1.

Example

a(4) = gcd(A338338(4), A338338(5), A338338(6)) = gcd(6, 3, 9) = 3.

Prog

(C) See Links section.

Crossrefs

Cf. A338338.

Sequence in context: A160183 A168534 A026807 * A179045 A106740 A178534

Adjacent sequences: A338437 A338438 A338439 * A338441 A338442 A338443

Keyword

nonn

Author

Rémy Sigrist, Oct 28 2020

Status

approved