A107410 - OEIS

%I #15 Mar 23 2024 13:51:56

%S 0,1,2,3,6,2,2,1,5,8,5,0,4,0,4,8,3,6,8,8,4,2,5,2,0,7,0,7,5,3,6,5,5,7,

%T 8,2,8,0,1,0,1,2,3,6,2,2,1,5,8,5,0,4,0,4,8,3,6,8,8,4,2,5,2,0,7,0,7,5,

%U 3,6,5,5,7,8,2,8,0,1,0,1,2,3,6,2,2,1,5,8,5,0,4,0,4,8,3,6,8,8,4,2,5,2,0,7,0

%N Each term is sum of three previous terms mod 9.

%C The sequence has period: {0,1,2,3,6,2,2,1,5,8,5,0,4,0,4,8,3,6,8,8,4,2,5,2,0,7,0,7,5,3,6,5,5,7,8,2,8,0,1} of length = 39.

%H <a href="/index/Rec#order_39">Index entries for linear recurrences with constant coefficients</a>, signature (0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1).

%F a(n) = mod(a(n-1)+a(n-2)+a(n-3), 9); a(1)=0, a(2)=1, a(3)=2.

%t s={a=0, b=1, c=2};Do[d=Mod[a+b+c, 9];s=Append[s, d];a=b;b=c;c=d, {m, 200}];s

%K nonn,easy

%O 0,3

%A _Zak Seidov_, May 25 2005