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A324904
The 2-adic valuation of A318466(n), where A318466(n) = 2*n OR sigma(n).
4
0, 0, 1, 0, 1, 2, 1, 0, 0, 1, 1, 2, 1, 2, 1, 0, 1, 0, 1, 1, 1, 2, 1, 2, 0, 1, 1, 3, 1, 2, 1, 0, 1, 1, 1, 0, 1, 2, 1, 1, 1, 2, 1, 2, 1, 2, 1, 2, 0, 0, 1, 1, 1, 2, 1, 3, 1, 1, 1, 3, 1, 2, 1, 0, 1, 2, 1, 1, 1, 2, 1, 0, 1, 1, 1, 2, 1, 2, 1, 1, 0, 1, 1, 3, 1, 2, 1, 2, 1, 1, 1, 3, 1, 2, 1, 2, 1, 0, 1, 0, 1, 2, 1, 1, 1
OFFSET
1,6
FORMULA
a(n) = A007814(A318466(n)).
a(n) = A324902(n) + A324903(n).
PROG
(PARI)
A318466(n) = bitor(2*n, sigma(n));
A324904(n) = valuation(A318466(n), 2);
(Python)
from sympy import divisor_sigma
def A324904(n): return (~(m:=n<<1|int(divisor_sigma(n))) & m-1).bit_length() # Chai Wah Wu, Jul 01 2022
KEYWORD
nonn
AUTHOR
Antti Karttunen, Mar 28 2019
STATUS
approved