A176555 Noncomposite concatenations of divisors of some k, ordered by k.

1, 13, 17, 139, 113, 13721, 131, 137, 167, 173, 179, 197, 1103, 1109, 111121, 1151, 1163, 1181, 1361183, 1193, 1373219, 1223, 1229, 1379237, 1277, 1283, 1307, 131133121363, 1367, 1373, 13127381, 1409, 1433, 1439, 13157471, 1487, 13163489

Offset: 1

Author

Jaroslav Krizek, Apr 20 2010

Keywords

• nonn
• base

Comments

Intersection of A037278 and A018252.

Examples

			For n = 6; a(6) = 13721 because A176553(6) = 21, and divisors of 21 are 1, 3, 7, 21; concatenation of divisors A037278(21) = 13721 is noncomposite number.
		

Formula

a(n) = A037278(A176553(n)).

Extensions

Extended and edited by Charles R Greathouse IV, Apr 27 2010