A323727 - OEIS

%I #18 Feb 03 2019 21:03:05

%S 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,

%T 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,

%U 9,8,7,8,9,10,11,11,10,10,9,10,10,10,11,11,10,9

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

%H Wikipedia, <a href="https://en.wikipedia.org/wiki/Tetration">Tetration</a>

%H <a href="/index/Com#complexity">Index to sequences related to the complexity of n</a>

%e 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.)

%Y Cf. A091333, A091334, A025280.

%K nonn

%O 1,2

%A _Robin Powell_, Jan 25 2019