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a(n) == {0,1,3,4,5,7,9,11} mod 12; n>0.
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%I #25 Mar 15 2024 02:19:15

%S 1,3,4,5,7,9,11,12,13,15,16,17,19,21,23,24,25,27,28,29,31,33,35,36,37,

%T 39,40,41,43,45,47,48,49,51,52,53,55,57,59,60,61,63,64,65,67,69,71,72,

%U 73,75,76,77,79,81,83,84,85,87,88,89,91,93,95,96,97,99

%N a(n) == {0,1,3,4,5,7,9,11} mod 12; n>0.

%C A141260 = characteristic function of A141259 such that A141260(n) = 1 if n is in A141259; 0 otherwise.

%H Vincenzo Librandi, <a href="/A141259/b141259.txt">Table of n, a(n) for n = 1..1000</a>

%H <a href="/index/Rec">Index entries for linear recurrences with constant coefficients</a>, signature (2,-2,2,-2,2,-2,2,-1).

%F a(n) = {0,1,3,4,5,7,9,11} mod 12; n>0.

%F G.f. (1+x)*(x^5+x^3+1) / ( (x^2+1)*(x^4+1)*(x-1)^2 ). - _R. J. Mathar_, Nov 21 2011

%e a(16) = 24, == 0 mod 12.

%t Select[Range[200],MemberQ[{0,1,3,4,5,7,9,11},Mod[#,12]]&] (* _Harvey P. Dale_, Feb 20 2014 *)

%o (Magma) [n: n in [1..100]|n mod 12 in {0, 1, 3, 4, 5, 7, 9, 11}]; // _Vincenzo Librandi_, Feb 22 2014

%Y Cf. A141260.

%K nonn

%O 1,2

%A _Gary W. Adamson_, Jun 18 2008

%E More terms from _Harvey P. Dale_, Feb 20 2014