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 A113806 #28 Nov 27 2024 07:25:38
%S A113806 6,8,20,22,34,36,48,50,62,64,76,78,90,92,104,106,118,120,132,134,146,
%T A113806 148,160,162,174,176,188,190,202,204,216,218,230,232,244,246,258,260,
%U A113806 272,274,286,288,300,302,314,316,328,330,342,344,356,358,370
%N A113806 Numbers that are congruent to {6, 8} mod 14.
%F A113806 a(n) = 14*n - a(n-1) - 14 (with a(1) = 6). - _Vincenzo Librandi_, Nov 13 2010
%F A113806 From _Wolfdieter Lang_, Dec 15 2011: (Start)
%F A113806 a(n) = 7*n-(7+5*(-1)^n)/2.
%F A113806 O.g.f.: 2*x*(3+x+3*x^2)/((1+x)*(1-x)^2).
%F A113806 See the _Bruno Berselli_ contribution under A113801. (End)
%F A113806 Sum_{n>=1} (-1)^(n+1)/a(n) = tan(Pi/14)*Pi/14. - _Amiram Eldar_, Dec 30 2021
%F A113806 From _Amiram Eldar_, Nov 25 2024: (Start)
%F A113806 Product_{n>=1} (1 - (-1)^n/a(n)) = sec(Pi/14).
%F A113806 Product_{n>=1} (1 + (-1)^n/a(n)) = cosec(Pi/7)*cosec(3*Pi/14)/4. (End)
%t A113806 Flatten[# + {6, 8} &/@ (14 Range[0, 30])] (* _Harvey P. Dale_, Jan 11 2011 *)
%Y A113806 Cf. A008589, A113801, A113802, A113803, A113804, A113805, A113807.
%K A113806 nonn,easy
%O A113806 1,1
%A A113806 _Giovanni Teofilatto_, Jan 22 2006