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Numbers that are congruent to {2, 4, 5, 6, 7} mod 8.
1

%I #16 Sep 08 2022 08:44:57

%S 2,4,5,6,7,10,12,13,14,15,18,20,21,22,23,26,28,29,30,31,34,36,37,38,

%T 39,42,44,45,46,47,50,52,53,54,55,58,60,61,62,63,66,68,69,70,71,74,76,

%U 77,78,79,82,84,85,86,87,90,92,93,94,95,98,100,101,102,103,106

%N Numbers that are congruent to {2, 4, 5, 6, 7} mod 8.

%H G. C. Greubel, <a href="/A047570/b047570.txt">Table of n, a(n) for n = 1..1000</a>

%H <a href="/index/Rec#order_06">Index entries for linear recurrences with constant coefficients</a>, signature (1,0,0,0,1,-1).

%F From _Chai Wah Wu_, May 30 2016: (Start)

%F a(n) = a(n-1) + a(n-5) - a(n-6).

%F G.f.: x*(x^5 + x^4 + x^3 + x^2 + 2*x + 2)/(x^6 - x^5 - x + 1). (End)

%t LinearRecurrence[{1, 0, 0, 0, 1, -1}, {2, 4, 5, 6, 7, 10} , 50] (* _G. C. Greubel_, May 30 2016 *)

%t Select[Range[200], MemberQ[{2, 4, 5, 6, 7}, Mod[#, 8]] &] (* _Vincenzo Librandi_ May 30 2016 *)

%o (Magma) [n: n in [0..150] | n mod 8 in [2,4,5,6,7]]; // _Vincenzo Librandi_, May 30 2016

%K nonn,easy

%O 1,1

%A _N. J. A. Sloane_