A073894 a(0)=1; a(n) for n > 0 is the smallest number not used earlier such that the concatenation of a(0),...,a(n) is a multiple of n+1.

1, 0, 2, 4, 5, 6, 9, 12, 15, 10, 11, 24, 25, 8, 30, 40, 41, 18, 28, 20, 27, 46, 31, 52, 50, 32, 38, 60, 61, 80, 55, 36, 44, 120, 45, 48, 78, 26, 64, 160, 93, 14, 23, 140, 95, 98, 21, 76, 51, 100, 56, 92, 84, 34, 85, 68, 3, 62, 115, 180, 81, 74, 88, 128, 75, 58, 72, 124, 134

Offset: 0

Author

Amarnath Murthy, Aug 17 2002

Keywords

• base
• nonn

Comments

Does every nonnegative integer eventually appear?

Examples

			Concatenation of a(0),...,a(6) is 1024569, not used so far are 3, 7, 8, 10, 11, 12, ..., the smallest of these that appended to 1024569 gives a multiple of 8 is 12: 102456912 = 8*12807114, hence a(7) = 12.
		

Crossrefs

Cf. A100769, A099552, A051883, A073893.

Extensions

Edited and extended by Klaus Brockhaus, Mar 28 2006