%I #17 Nov 17 2022 05:27:01
%S 1,1,4,1,4,4,16,1,4,4,16,4,16,16,64,1,4,4,16,4,16,16,64,4,16,16,64,16,
%T 64,64,256,1,4,4,16,4,16,16,64,4,16,16,64,16,64,64,256,4,16,16,64,16,
%U 64,64,256,16,64,64,256,64,256,256,1024,1,4,4,16,4,16,16,64,4,16,16,64,16,64
%N a(n) = 4^(wt(n) - 1) where wt(n) = A000120(n).
%e From _Omar E. Pol_, Jul 21 2009: (Start)
%e If written as a triangle:
%e 1;
%e 1,4;
%e 1,4,4,16;
%e 1,4,4,16,4,16,16,64;
%e 1,4,4,16,4,16,16,64,4,16,16,64,16,64,64,256;
%e 1,4,4,16,4,16,16,64,4,16,16,64,16,64,64,256,4,16,16,64,16,64,64,256,16,64,...
%e (End)
%o (Python 3.10+)
%o def A151783(n): return 1<<(n.bit_count()-1<<1) # _Chai Wah Wu_, Nov 15 2022
%Y Cf. A000120, A048881, A048896, A147610, A151780.
%Y Cf. A000302, A102376. [_Omar E. Pol_, Jul 21 2009]
%Y A102376 is a very similar sequence.
%K nonn
%O 1,3
%A _N. J. A. Sloane_, Jun 25 2009
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