A084301 - OEIS

%I #26 May 25 2020 09:57:03

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

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

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

%N a(n) = sigma(n) mod 6.

%H Antti Karttunen, <a href="/A084301/b084301.txt">Table of n, a(n) for n = 1..16384</a>

%H <a href="/index/Su#sums_of_divisors">Index entries for sequences related to sums of divisors</a>

%F a(n) = A010875(A000203(n)). - _Antti Karttunen_, Nov 07 2017

%p A084301:= n-> (numtheory[sigma](n) mod 6):

%p seq (A084301(n), n=1..105); # _Jani Melik_, Jan 26 2011

%t Table[Mod[DivisorSigma[1,n],6],{n,120}]  (* _Harvey P. Dale_, Apr 07 2011 *)

%o (PARI) a(n)=sigma(n)%6 \\ _Charles R Greathouse IV_, Mar 09 2014

%Y Cf. A000203, A010875, A054763, A084299, A084300.

%Y Sequences sigma(n) mod k: A053866 (k=2), A074941 (k=3), A105824 (k=4), A105825 (k=5), A084301 (k=6), A105826 (k=7), A105827 (k=8).

%Y Cf. A074627 (locations of 0), A074628 (locations of 2), A067051 (locations of 3), A074630 (locations of 4), A074384 (locations of 5).

%K easy,nonn

%O 1,2

%A _Labos Elemer_, Jun 02 2003