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A318506
a(n) = A032742(n) OR A001065(n)-A032742(n), where OR is bitwise-or (A003986) and A001065 = sum of proper divisors and A032742 = the largest proper divisor of n.
6
1, 1, 1, 3, 1, 3, 1, 7, 3, 7, 1, 14, 1, 7, 5, 15, 1, 13, 1, 14, 7, 11, 1, 28, 5, 15, 13, 14, 1, 31, 1, 31, 15, 19, 7, 55, 1, 19, 13, 30, 1, 53, 1, 22, 31, 23, 1, 60, 7, 27, 21, 30, 1, 63, 15, 60, 23, 31, 1, 94, 1, 31, 21, 63, 15, 45, 1, 58, 23, 39, 1, 119, 1, 39, 25, 62, 11, 55, 1, 106, 31, 43, 1, 106, 23, 43, 29, 60, 1, 111, 13, 62, 31
OFFSET
1,4
FORMULA
a(n) = A003986(A032742(n), A318505(n)).
For n > 1, a(n) = A001065(n) - A318508(n).
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));
A318506(n) = bitor(A318505(n), A032742(n));
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Antti Karttunen, Aug 28 2018
STATUS
approved