A318457 - OEIS

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A318457

a(n) = n XOR A001065(n), where XOR is bitwise-xor (A003987) and A001065 = sum of proper divisors.

1, 3, 2, 7, 4, 0, 6, 15, 13, 2, 10, 28, 12, 4, 6, 31, 16, 7, 18, 2, 30, 24, 22, 60, 31, 10, 22, 0, 28, 52, 30, 63, 46, 54, 46, 19, 36, 48, 54, 26, 40, 28, 42, 4, 12, 52, 46, 124, 57, 25, 38, 26, 52, 116, 38, 120, 46, 26, 58, 80, 60, 28, 22, 127, 82, 12, 66, 126, 94, 12, 70, 51, 72, 98, 122, 12, 94, 20, 78, 58, 121, 126, 82, 216, 66

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,2

LINKS

Antti Karttunen, Table of n, a(n) for n = 1..65537

Index entries for sequences related to binary expansion of n

Index entries for sequences related to sigma(n)

FORMULA

a(n) = A003987(n, A001065(n)).

a(n) = A000203(n) - 2*A318458(n).

MATHEMATICA

Array[BitXor[#, DivisorSigma[1, #] - #] &, 100] (* Paolo Xausa, Dec 16 2024 *)