A206960 a(0)=0, a(1)=1, for n>1, a(n) = n<*>n, where k<*>m = k<+>k<+>...<+>k is the m-1-fold iteration of the operation <+> defined in A206853.

0, 1, 4, 9, 31, 66, 190, 385, 1022, 2055, 5112, 10242, 24572, 49153, 114686, 229377, 524287, 1048590, 2359281, 4718599, 10485753, 20971521, 46137342, 92274689, 201326590, 402653191, 872415224, 1744830466, 3758096380, 7516192769, 16106127358, 32212254721

Offset: 0

Author

Vladimir Shevelev and Konstantin Shukhmin (shukhmin(AT)callsouth.net.nz), Feb 14 2012

Keywords

• nonn
• base

Comments

A Hamming's analog of n^2.

Crossrefs

Cf. A205509, A205510, A205511, A205302, A205649, A205533, A122565, A206852, A206853.

Programs

Mathematica

f[n_,k_]:=Module[{i=n+1},While[Count[IntegerDigits[BitXor[n,i],2],1]!=k,i++]; i]; Join[{0,1},Table[Nest[f[#,k]&,k,k-1],{k,2,18}]] (* Jayanta Basu, May 26 2013 *)

Formula

A010060(a(n)) = A010060(n). - Vladimir Shevelev and Alois P. Heinz, Feb 17 2012

Extensions

a(11)-a(31) from Alois P. Heinz, Feb 16 2012