A318508 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.

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, 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, 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

Offset: 1

Author

Antti Karttunen, Aug 28 2018

Keywords

• nonn
• base

Links

• Antti Karttunen, Table of n, a(n) for n = 1..65537
• Index entries for sequences related to binary expansion of n

Crossrefs

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

Cf. also A318457, A318517.

Programs

PARI

A001065(n) = (sigma(n)-n);
A032742(n) = if(1==n,n,n/vecmin(factor(n)[,1]));
A318505(n) = if(1==n,0,A001065(n)-A032742(n));
A318508(n) = bitand(A318505(n),A032742(n));

Formula

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

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