A162908 Pairs of central divisors of A089229(n).

2, 3, 2, 4, 2, 5, 3, 4, 2, 7, 3, 5, 3, 6, 4, 5, 3, 7, 2, 11, 4, 6, 2, 13, 3, 9, 4, 7, 5, 6, 4, 8, 3, 11, 2, 17, 5, 7, 2, 19, 3, 13, 5, 8, 6, 7, 4, 11, 5, 9, 2, 23, 6, 8, 5, 10, 3, 17, 4, 13, 6, 9, 5, 11, 7, 8, 3, 19, 2, 29, 6, 10, 2, 31, 7, 9, 5, 13, 6, 11, 4, 17, 3, 23, 7, 10, 8, 9, 2, 37, 5, 15, 4, 19

Offset: 1

Author

Juri-Stepan Gerasimov, Jul 17 2009

Keywords

• nonn
• easy

Comments

The central divisors are the two complementary divisors closest to the square

root of a number, as tabulated in A162348.

Examples

			a(1)=2 and a(2)=3 since A089229(1)=6 with divisors 1, 2, 3, 4.
a(3)=2 and a(4)=4 since A089229(2)=8 with divisors 1, 2, 4, 8.
a(5)=2 and a(6)=5 since A089229(3)=10 with divisors 1, 2, 5, 10.
		

Crossrefs

Cf. A089229, A162361.

Formula

a(2n-1)= A033676(A089229(n)). a(2n)=A033677(A089229(n)). - R. J. Mathar, Jul 19 2009

Extensions

Missing pairs inserted by R. J. Mathar, Jul 19 2009