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A324831 Number of divisors d of n such that A323243(d) == 1 (mod 3). 6

%I #7 Mar 16 2019 21:46:24

%S 0,1,0,2,1,1,0,2,0,3,1,2,0,1,1,2,1,1,0,4,0,2,1,2,2,1,0,2,0,3,1,2,1,2,

%T 1,3,0,1,0,4,1,1,0,3,1,2,1,2,0,5,1,2,0,1,3,2,0,1,1,4,0,2,0,2,1,2,1,4,

%U 1,3,0,3,1,1,2,2,1,2,0,4,0,2,1,3,2,1,0,3,0,3,0,4,1,2,1,2,1,1,1,6,0,2,1,2,1

%N Number of divisors d of n such that A323243(d) == 1 (mod 3).

%H Antti Karttunen, <a href="/A324831/b324831.txt">Table of n, a(n) for n = 1..10000</a> (based on Hans Havermann's factorization of A156552)

%H <a href="/index/Bi#binary">Index entries for sequences related to binary expansion of n</a>

%H <a href="/index/Pri#prime_indices">Index entries for sequences computed from indices in prime factorization</a>

%H <a href="/index/Si#SIGMAN">Index entries for sequences related to sigma(n)</a>

%F a(n) = A000005(n) - (A324830(n) + A324832(n)).

%F For all n >= 1, a(A000040(n)) = A000035(n).

%o (PARI) A324831(n) = sumdiv(n,d,(1==(A323243(d))%3));

%Y Cf. A000005, A000203, A156552, A323243, A324830, A324832.

%K nonn

%O 1,4

%A _Antti Karttunen_, Mar 16 2019

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Last modified March 28 13:18 EDT 2024. Contains 371254 sequences. (Running on oeis4.)