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Length of longest contiguous block of 1's in binary expansion of n^2.
7

%I #7 Nov 28 2014 14:05:59

%S 0,1,1,1,1,2,1,2,1,1,2,4,1,1,2,3,1,1,1,2,2,3,4,1,1,3,1,2,2,2,3,4,1,1,

%T 1,2,1,2,2,5,2,2,3,3,4,6,1,1,1,2,3,1,1,5,2,4,2,2,2,2,3,3,4,5,1,1,1,2,

%U 1,2,2,3,1,2,2,6,2,3,5,2,2,2,2,3,3,3,3,3,4,4,6,2,1,3,1,2,1,2,2,2,3,5

%N Length of longest contiguous block of 1's in binary expansion of n^2.

%C a(n) = A038374(A000290(n)).

%H Harvey P. Dale, <a href="/A090001/b090001.txt">Table of n, a(n) for n = 0..1000</a>

%t Join[{0},Table[Max[Length/@Select[Split[IntegerDigits[n^2,2]], MemberQ[ #,1]&]],{n,110}]] (* _Harvey P. Dale_, Nov 28 2014 *)

%Y Cf. A000120, A090003, A090002, A090000, A089998, A090047.

%K nonn,base

%O 0,6

%A _Reinhard Zumkeller_, Nov 20 2003