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 A020793 #55 Aug 06 2024 09:57:18
%S A020793 1,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,
%T A020793 6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,
%U A020793 6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6
%N A020793 Decimal expansion of 1/6.
%C A020793 Except for the first term identical to A010722, A040006 and A021019. Except for the first terms the same as A021028, A021100, A021388, A071279, A101272, A168608, A177057,... - _M. F. Hasler_, Oct 24 2011
%C A020793 Decimal expansion of gamma(1) = 5/3 (with offset 1), where gamma(n) = Cp(n)/Cv(n) = is the n-th Poisson's constant. For the definition of Cp and Cv see A272002. - _Natan Arie Consigli_, Jul 10 2016
%D A020793 Calvin C. Clawson, Mathematical Mysteries, The Beauty and Magic of Numbers, Springer, 2013, see p. 224.
%H A020793 Wikipedia, <a href="https://en.wikipedia.org/wiki/Heat_capacity_ratio">Poisson's constant</a>.
%H A020793 <a href="/index/Rec#order_01">Index entries for linear recurrences with constant coefficients</a>, signature (1).
%F A020793 a(n) = 6^n mod 10. - _Zerinvary Lajos_, Nov 26 2009
%F A020793 Equals Sum_{k>=1} 1/7^k. - _Bruno Berselli_, Jan 03 2014
%F A020793 10 * 1/6 = 5/3 = (5/2 R)/(3/2 R) = Cp(1)/Cv(1) = A272002/A272001, with R = A081822 (or A070064). - _Natan Arie Consigli_, Jul 10 2016
%F A020793 G.f.: (1 + 5*x)/(1 - x). - _Ilya Gutkovskiy_, Jul 10 2016
%F A020793 Equals Sum_{k>=1} 1/(k*Pi)^2. - _Maciej Kaniewski_, Sep 14 2017
%F A020793 Equals Sum_{k>=1} (zeta(2*k)-1)/4^k. - _Amiram Eldar_, Jun 08 2021
%F A020793 K_{n>=2} 2*n/(2*n - 3) = 5/3. (see Clawson at p. 224). - _Stefano Spezia_, Jul 01 2024
%F A020793 E.g.f.: 6*exp(x) - 5. - _Elmo R. Oliveira_, Aug 05 2024
%t A020793 RealDigits[1/6,10,120][[1]] (* or *) PadRight[{1},120,{6}] (* _Harvey P. Dale_, Dec 30 2018 *)
%o A020793 (PARI) a(n)=6-5*!n \\ _M. F. Hasler_, Oct 24 2011
%Y A020793 Cf. A010722, A021019, A021028, A021100, A021388, A040006, A070064, A071279, A081822, A101272, A168608, A177057, A272001, A272002.
%K A020793 nonn,cons,easy
%O A020793 0,2
%A A020793 _N. J. A. Sloane_