A064065 n-th step is to add a(n) to each previous number a(k) (excluding itself, i.e., k < n) to produce n more terms of the sequence, starting with a(0)=0, a(1)=1.

0, 1, 1, 1, 2, 1, 2, 2, 2, 3, 3, 3, 1, 2, 2, 2, 3, 2, 3, 3, 3, 4, 3, 2, 3, 3, 3, 4, 3, 4, 2, 3, 3, 3, 4, 3, 4, 4, 3, 4, 4, 4, 5, 4, 5, 5, 5, 3, 4, 4, 4, 5, 4, 5, 5, 5, 6, 3, 4, 4, 4, 5, 4, 5, 5, 5, 6, 6, 1, 2, 2, 2, 3, 2, 3, 3, 3, 4, 4, 4, 2, 3, 3, 3, 4, 3, 4, 4, 4, 5, 5, 5, 3, 2, 3, 3, 3, 4, 3, 4, 4, 4, 5, 5, 5

Offset: 0

Author

Henry Bottomley, Aug 31 2001

Keywords

• nonn

Comments

Each positive number appears an infinite number of times: e.g., a(k)=1 whenever k-1 is in A006894.

Examples

			Start with (0,1). So after initial step have (0, *1*, 0+1 = 1), then (0, 1, *1*, 0+1 = 1, 1+1 = 2), then (0, 1, 1, *1*, 2, 0+1 = 1, 1+1 = 2, 1+1 = 2), then (0, 1, 1, 1, *2*, 1, 2, 2, 0+2 = 2, 1+2 = 3, 1+2 = 3, 1+2 = 3), etc.
		

Crossrefs

Cf. A064064, A064066, A064067.