cp's OEIS Frontend

A328107 Binary weight of A327973.

%I A328107 #8 Oct 05 2019 18:21:38
%S A328107 2,4,5,6,7,8,9,13,11,13,13,14,17,18,19,23,20,23,24,27,26,24,23,30,31,
%T A328107 29,29,31,36,35,36,37,35,34,35,42,40,46,41,50,54,48,52,47,47,53,47,51,
%U A328107 51,54,48,51,60,55,56,64,61,60,59,68,71,67,65,78,64,63,68,72,70,74,79,89,85,77,85,76,79,83,78,90,97,82,87,81
%N A328107 Binary weight of A327973.
%H A328107 Antti Karttunen, <a href="/A328107/b328107.txt">Table of n, a(n) for n = 1..16384</a>
%H A328107 <a href="/index/Bi#binary">Index entries for sequences related to binary expansion of n</a>
%H A328107 <a href="/index/Ce#cell">Index entries for sequences related to cellular automata</a>
%F A328107 a(n) = A000120(A327973(n)) = A000120(A110240(n) XOR 2*A110240(n-1)).
%o A328107 (PARI)
%o A328107 A269160(n) = bitxor(n, bitor(2*n, 4*n)); \\ From A269160.
%o A328107 A110240(n) = if(!n,1,A269160(A110240(n-1)));
%o A328107 A327973(n) = bitxor(A110240(n), 2*A110240(n-1));
%o A328107 A328107(n) = hammingweight(bitxor(A110240(n), 2*A110240(n-1)));
%o A328107 \\ Use this one for writing b-files:
%o A328107 A328107write(up_to) = { my(s=1, t, n=0); for(n=1,up_to, t = A269160(s); write("b328107.txt", n, " ", hammingweight(bitxor(2*s, t))); s = t); };
%Y A328107 Cf. A000120, A110240, A269160, A327973.
%Y A328107 Cf. also A070952, A328105, A328106, A328108, A328109.
%K A328107 nonn
%O A328107 1,1
%A A328107 _Antti Karttunen_, Oct 05 2019