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%I #12 Jul 02 2022 01:52:33
%S 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,
%T 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,
%U 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
%N The 2-adic valuation of A318466(n), where A318466(n) = 2*n OR sigma(n).
%H Antti Karttunen, <a href="/A324904/b324904.txt">Table of n, a(n) for n = 1..65537</a>
%H <a href="/index/Bi#binary">Index entries for sequences related to binary expansion of n</a>
%H <a href="/index/Si#SIGMAN">Index entries for sequences related to sigma(n)</a>
%F a(n) = A007814(A318466(n)).
%F a(n) = A324902(n) + A324903(n).
%o (PARI)
%o A318466(n) = bitor(2*n, sigma(n));
%o A324904(n) = valuation(A318466(n),2);
%o (Python)
%o from sympy import divisor_sigma
%o def A324904(n): return (~(m:=n<<1|int(divisor_sigma(n))) & m-1).bit_length() # _Chai Wah Wu_, Jul 01 2022
%Y Cf. A000203, A001065, A003986, A007814, A318466, A324884, A324902, A324903, A324906.
%K nonn
%O 1,6
%A _Antti Karttunen_, Mar 28 2019
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