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 A354343 #16 Nov 03 2024 17:46:01
%S A354343 1,6,19,37,61,91,127,169,217,271,331,397,469,547,631,721,817,919,1027,
%T A354343 1141,1261,1387,1519,1657,1801,1951,2107,2269,2437,2611,2791,2977,
%U A354343 3169,3367,3571,3781,3997,4219,4447,4681,4921,5167,5419,5677,5941,6211,6487,6769,7057,7351,7651,7957
%N A354343 Number of distinct sums of n complex 6th power roots of unity.
%H A354343 <a href="/index/Rec#order_03">Index entries for linear recurrences with constant coefficients</a>, signature (3,-3,1).
%F A354343 For n >= 2, a(n) = 3*n^2 + 3*n + 1 = A003215(n).
%F A354343 For n >= 5, a(n) = 3*a(n-1) - 3*a(n-2) + a(n-3).
%F A354343 G.f. (1 + 3*x + 4*x^2 - 3*x^3 + x^4) / (1 - x)^3.
%t A354343 LinearRecurrence[{3,-3,1},{1,6,19,37,61},60] (* _Harvey P. Dale_, Nov 03 2024 *)
%o A354343 (PARI) a(n)=if(n==1, 6, 3*n*(n+1)+1) \\ _Charles R Greathouse IV_, Aug 15 2022
%Y A354343 Same as A003215 except for a(1) = 6.
%Y A354343 Row 6 of A299807.
%Y A354343 Cf. A000012, A000027, A000217, A000290, A000332, A000579, A014820, A103314, A107754, A107861, A108380, A107848, A107753, A108381, A143008, A299754.
%K A354343 nonn,easy
%O A354343 0,2
%A A354343 _Max Alekseyev_, Aug 15 2022