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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.
9
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
0,3
COMMENTS
A Hamming's analog of n^2.
FORMULA
A010060(a(n)) = A010060(n). - Vladimir Shevelev and Alois P. Heinz, Feb 17 2012
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 *)
KEYWORD
nonn,base
AUTHOR
Vladimir Shevelev and Konstantin Shukhmin (shukhmin(AT)callsouth.net.nz), Feb 14 2012
EXTENSIONS
a(11)-a(31) from Alois P. Heinz, Feb 16 2012
STATUS
approved