This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A047324 #23 Jan 10 2023 11:46:45
%S A047324 0,2,5,6,7,9,12,13,14,16,19,20,21,23,26,27,28,30,33,34,35,37,40,41,42,
%T A047324 44,47,48,49,51,54,55,56,58,61,62,63,65,68,69,70,72,75,76,77,79,82,83,
%U A047324 84,86,89,90,91,93,96,97,98,100,103,104,105,107,110,111
%N A047324 Numbers that are congruent to {0, 2, 5, 6} mod 7.
%H A047324 <a href="/index/Rec#order_05">Index entries for linear recurrences with constant coefficients</a>, signature (1,0,0,1,-1).
%F A047324 G.f.: x^2*(2+3*x+x^2+x^3) / ( (1+x)*(1+x^2)*(x-1)^2 ). - _R. J. Mathar_, Dec 04 2011
%F A047324 From _Wesley Ivan Hurt_, Jun 03 2016: (Start)
%F A047324 a(n) = a(n-1) + a(n-4) - a(n-5) for n > 5.
%F A047324 a(n) = (14*n - 9 - i^(2*n) + (1 - 3*i)*i^(-n) + (1 + 3*i)*i^n)/8 where i = sqrt(-1).
%F A047324 a(2k) = A047276(k), a(2k-1) = A047382(k). (End)
%F A047324 E.g.f.: (4 - 3*sin(x) + cos(x) + (7*x - 4)*sinh(x) + (7*x - 5)*cosh(x))/4. - _Ilya Gutkovskiy_, Jun 04 2016
%p A047324 A047324:=n->(14*n-9-I^(2*n)+(1-3*I)*I^(-n)+(1+3*I)*I^n)/8: seq(A047324(n), n=1..100); # _Wesley Ivan Hurt_, Jun 03 2016
%t A047324 Table[(14n - 9 - I^(2n) + (1 - 3 * I) * I^(-n) + (1 + 3 * I) * I^n)/8, {n, 80}] (* _Wesley Ivan Hurt_, Jun 03 2016 *)
%t A047324 Flatten[Table[7n + {0, 2, 5, 6}, {n, 0, 15}]] (* _Alonso del Arte_, Jun 04 2016 *)
%t A047324 LinearRecurrence[{1,0,0,1,-1},{0,2,5,6,7},80] (* _Harvey P. Dale_, Jan 10 2023 *)
%o A047324 (Magma) [n : n in [0..150] | n mod 7 in [0, 2, 5, 6]]; // _Wesley Ivan Hurt_, Jun 03 2016
%Y A047324 Cf. A047276, A047382.
%K A047324 nonn,easy
%O A047324 1,2
%A A047324 _N. J. A. Sloane_