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a(n) = (n^2+n+4)/2, modulo 10.
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%I #13 Oct 19 2017 03:14:34

%S 2,3,5,8,2,7,3,0,8,7,7,8,0,3,7,2,8,5,3,2,2,3,5,8,2,7,3,0,8,7,7,8,0,3,

%T 7,2,8,5,3,2,2,3,5,8,2,7,3,0,8,7,7,8,0,3,7,2,8,5,3,2,2,3,5,8,2,7,3,0,

%U 8,7,7,8,0,3,7,2,8,5,3,2,2,3,5,8,2,7,3,0,8,7,7,8,0,3,7,2,8,5,3,2,2,3,5,8,2

%N a(n) = (n^2+n+4)/2, modulo 10.

%C This periodic sequence equals A008954(n)+2 modulo 10 and also A061501(n+1)+1 modulo 10.

%H <a href="/index/Rec#order_15">Index entries for linear recurrences with constant coefficients</a>, signature (0, 0, 0, 0, 1, 0, 0, 0, 0, -1, 0, 0, 0, 0, 1).

%F a(0)=2, a(1)=3, a(2)=5, a(3)=8, a(4)=2, a(5)=7, a(6)=3, a(7)=0, a(8)=8, a(9)=7, a(10)=7, a(11)=8, a(12)=0, a(13)=3, a(14)=7, a(n)=a(n-5)-a(n-10)+ a(n-15). - _Harvey P. Dale_, Nov 16 2012

%t Table[Mod[(n^2+n+4)/2,10],{n,0,110}] (* or *) LinearRecurrence[ {0,0,0,0,1,0,0,0,0,-1,0,0,0,0,1},{2,3,5,8,2,7,3,0,8,7,7,8,0,3,7},110] (* _Harvey P. Dale_, Nov 16 2012 *)

%Y Cf. A008954, A061501.

%K nonn,easy,less

%O 0,1

%A _Cino Hilliard_, Aug 02 2004

%E Edited by _Don Reble_, Apr 16 2007