A080717 Let S(0) = 1; obtain S(k) from S(k-1) by applying 1 -> 2, 2 -> 31, 3 -> 332; sequence is S(0), S(1), S(2), ...

2, 3, 1, 3, 3, 2, 2, 3, 3, 2, 3, 3, 2, 3, 1, 3, 1, 3, 3, 2, 3, 3, 2, 3, 1, 3, 3, 2, 3, 3, 2, 3, 1, 3, 3, 2, 2, 3, 3, 2, 2, 3, 3, 2, 3, 3, 2, 3, 1, 3, 3, 2, 3, 3, 2, 3, 1, 3, 3, 2, 2, 3, 3, 2, 3, 3, 2, 3, 1, 3, 3, 2, 3, 3, 2, 3, 1, 3, 3, 2, 2, 3, 3, 2, 3, 3, 2, 3, 1, 3, 1, 3, 3, 2, 3, 3, 2, 3, 1, 3, 1, 3, 3, 2, 3

Offset: 1

Author

Matthew Vandermast, Mar 06 2003

Keywords

• easy
• nonn

Comments

a(n) = A080704(n+1) - A080704(n). Sum of first n terms + 2 = A080704(n+1).

Examples

			2 31 3322 3323323131 ...
		

Programs

Mathematica

Flatten[ Table[ Nest[ Flatten[ # /. {1 -> {2}, 2 -> {3, 1}, 3 -> {3, 3, 2}}] &, {2}, n], {n, 0, 6}]] (* Robert G. Wilson v, May 07 2005 *)

Extensions

Edited by Robert G. Wilson v, May 07 2005