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A169813
a(n) = n XOR sigma(n), where sigma(n) is the number of divisors of n, A000203.
7
0, 1, 7, 3, 3, 10, 15, 7, 4, 24, 7, 16, 3, 22, 23, 15, 3, 53, 7, 62, 53, 50, 15, 36, 6, 48, 51, 36, 3, 86, 63, 31, 17, 20, 19, 127, 3, 26, 31, 114, 3, 74, 7, 120, 99, 102, 31, 76, 8, 111, 123, 86, 3, 78, 127, 64, 105, 96, 7, 148, 3, 94, 87, 63, 21, 210, 7, 58, 37, 214, 15, 139, 3, 56
OFFSET
1,3
PROG
(Scheme) (define (A169813 n) (A003987bi n (A000203 n))) ;; Where A003987bi implements the bitwise-XOR, A003987 and code for A000203 can be found under that entry. - Antti Karttunen, Nov 25 2017
(PARI) a(n) = bitxor(n, sigma(n)); \\ Michel Marcus, Nov 25 2017
KEYWORD
nonn,look
AUTHOR
N. J. A. Sloane, May 28 2010
STATUS
approved