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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.
7
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
1,6
FORMULA
a(n) = A004198(A032742(n), A318505(n)).
For n > 1, a(n) = A001065(n) - A318506(n) = (A001065(n) - A318507(n))/2.
PROG
(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));
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Antti Karttunen, Aug 28 2018
STATUS
approved