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A318456
a(n) = n OR A001065(n), where OR is bitwise-or (A003986) and A001065 = sum of proper divisors.
12
1, 3, 3, 7, 5, 6, 7, 15, 13, 10, 11, 28, 13, 14, 15, 31, 17, 23, 19, 22, 31, 30, 23, 60, 31, 26, 31, 28, 29, 62, 31, 63, 47, 54, 47, 55, 37, 54, 55, 58, 41, 62, 43, 44, 45, 62, 47, 124, 57, 59, 55, 62, 53, 118, 55, 120, 63, 58, 59, 124, 61, 62, 63, 127, 83, 78, 67, 126, 95, 78, 71, 123, 73, 106, 123, 76, 95, 94, 79, 122, 121, 126, 83
OFFSET
1,2
FORMULA
a(n) = A003986(n, A001065(n)).
a(n) = A000203(n) - A318458(n).
MATHEMATICA
Array[BitOr[#, DivisorSigma[1, #] - #] &, 100] (* Paolo Xausa, Mar 11 2024 *)
PROG
(PARI) A318456(n) = bitor(n, sigma(n)-n);
(Python)
from sympy import divisor_sigma
def A318456(n): return n|divisor_sigma(n)-n # Chai Wah Wu, Jul 01 2022
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Antti Karttunen, Aug 26 2018
STATUS
approved