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The largest proper divisor of n, reduced modulo 4, with a(1) = 1.
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%I #13 Apr 26 2022 07:10:46

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

%T 3,2,1,3,1,0,1,1,1,2,3,3,1,0,3,1,1,2,1,3,3,0,3,1,1,2,1,3,1,0,1,1,1,2,

%U 3,3,1,0,1,1,1,2,3,3,1,0,3,1,1,2,1,3,1,0,1,1,1,2,3,3,3,0,1,1,1,2,1,3,1,0,3

%N The largest proper divisor of n, reduced modulo 4, with a(1) = 1.

%H Antti Karttunen, <a href="/A353490/b353490.txt">Table of n, a(n) for n = 1..65537</a>

%F a(n) = A010873(A032742(n)).

%o (PARI)

%o A032742(n) = if(1==n,n,n/vecmin(factor(n)[,1]));

%o A353490(n) = (A032742(n)%4);

%o (Python)

%o from sympy import factorint

%o def a(n): return 1 if n==1 else (n//min(factorint(n)))%4

%o print([a(n) for n in range(1, 106)]) # _Michael S. Branicky_, Apr 26 2022

%Y Cf. A032742, A353491, A353492.

%K nonn

%O 1,4

%A _Antti Karttunen_, Apr 22 2022