A323727 Number of 1's required to build n using +, -, *, ^ and tetration.

1, 2, 3, 4, 5, 5, 6, 5, 5, 6, 7, 7, 8, 7, 6, 5, 6, 7, 8, 8, 9, 9, 9, 8, 7, 6, 5, 6, 7, 8, 8, 7, 8, 9, 8, 7, 8, 9, 10, 10, 11, 11, 10, 11, 10, 10, 9, 8, 8, 9, 10, 9, 8, 7, 8, 9, 10, 10, 11, 11, 10, 9, 8, 7, 8, 9, 10, 11, 11, 10, 10, 9, 10, 10, 10, 11, 11, 10, 9

Offset: 1

Author

Robin Powell, Jan 25 2019

Keywords

• nonn

Examples

			a(14) = 7 because 14 = (1+1)^^(1+1+1)-1-1. (Note that 14 is also the smallest index at which this sequence differs from A091334.)
		

Links

• Wikipedia, Tetration
• Index to sequences related to the complexity of n

Crossrefs

Cf. A091333, A091334, A025280.