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A324902
The 2-adic valuation of A318456(n), where A318456(n) = n OR (sigma(n)-n).
3
0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 2, 0, 1, 0, 0, 0, 0, 0, 1, 0, 1, 0, 2, 0, 1, 0, 2, 0, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 1, 0, 1, 0, 2, 0, 1, 0, 2, 0, 0, 0, 1, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0, 0, 0, 1, 0, 1, 0, 1, 0, 0, 0, 1, 0, 2, 0, 1, 0, 1, 0, 1, 0, 2, 0, 1, 0, 2, 0, 1, 0, 2, 0, 1, 0, 2, 0, 0, 0, 0, 0, 1, 0, 1, 0
OFFSET
1,12
FORMULA
a(n) = A007814(A318456(n)).
a(n) = A324904(n) - A324903(n).
PROG
(PARI)
A318456(n) = bitor(n, sigma(n)-n);
A324902(n) = valuation(A318456(n), 2);
(Python)
from sympy import divisor_sigma
def A324902(n): return (~(m:=n|int(divisor_sigma(n))-n) & m-1).bit_length() # Chai Wah Wu, Jul 01 2022
KEYWORD
nonn
AUTHOR
Antti Karttunen, Mar 28 2019
STATUS
approved