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a(n) = A032742(n) AND A001065(n)-A032742(n), where AND is bitwise-and (A004198) and A001065 = sum of proper divisors and A032742 = the largest proper divisor of n.
7

%I #6 Aug 28 2018 15:59:12

%S 0,0,0,0,0,3,0,0,1,1,0,2,0,3,4,0,0,8,0,8,4,3,0,8,1,1,0,14,0,11,0,0,0,

%T 1,6,0,0,3,4,20,0,1,0,18,2,3,0,16,1,16,0,16,0,3,2,4,0,1,0,14,0,3,20,0,

%U 4,33,0,0,4,35,0,4,0,1,24,2,8,35,0,0,9,1,0,34,0,3,4,32,0,33,8,14,4,3,2,32,0,16,0,2,0,51,0,52,32

%N a(n) = A032742(n) AND A001065(n)-A032742(n), where AND is bitwise-and (A004198) and A001065 = sum of proper divisors and A032742 = the largest proper divisor of n.

%H Antti Karttunen, <a href="/A318508/b318508.txt">Table of n, a(n) for n = 1..65537</a>

%H <a href="/index/Bi#binary">Index entries for sequences related to binary expansion of n</a>

%F a(n) = A004198(A032742(n), A318505(n)).

%F For n > 1, a(n) = A001065(n) - A318506(n) = (A001065(n) - A318507(n))/2.

%o (PARI)

%o A001065(n) = (sigma(n)-n);

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

%o A318505(n) = if(1==n,0,A001065(n)-A032742(n));

%o A318508(n) = bitand(A318505(n),A032742(n));

%Y Cf. A001065, A004198, A032742, A318505, A318506, A318507.

%Y Cf. also A318457, A318517.

%K nonn,base

%O 1,6

%A _Antti Karttunen_, Aug 28 2018