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A268723 Main diagonal of A268725: a(n) = A003188(A006068(n)^2), where A003188 is binary Gray code and A006068 is its inverse.

%I A268723 #11 Jun 30 2022 14:43:51
%S A268723 0,1,13,6,41,54,24,21,145,166,216,253,96,121,69,86,545,582,664,749,
%T A268723 864,841,949,1014,384,433,477,486,793,278,344,357,2113,2182,2328,2509,
%U A268723 2656,2793,2901,2998,3456,3537,3901,3366,3641,3798,4056,3973,1536,1633,1709,1734,1801,1910,1944,2037,3313,3174,1112,1053
%N A268723 Main diagonal of A268725: a(n) = A003188(A006068(n)^2), where A003188 is binary Gray code and A006068 is its inverse.
%H A268723 Antti Karttunen, <a href="/A268723/b268723.txt">Table of n, a(n) for n = 0..8191</a>
%F A268723 a(n) = A003188(A000290(A006068(n))).
%o A268723 (Scheme) (define (A268723 n) (A003188 (A000290 (A006068 n))))
%o A268723 (Python)
%o A268723 def A268723(n):
%o A268723     k, m = n, n>>1
%o A268723     while m > 0:
%o A268723         k ^= m
%o A268723         m >>= 1
%o A268723     return (a:=k**2)^ a>>1 # _Chai Wah Wu_, Jun 30 2022
%Y A268723 Cf. A000290, A003188, A006068.
%Y A268723 Main diagonal of array A268725.
%K A268723 nonn
%O A268723 0,3
%A A268723 _Antti Karttunen_, Feb 13 2016