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 A367705 #17 Jan 01 2024 01:59:26
%S A367705 1,5,11,7,17,23,13,29,35,19,41,47,25,53,59,31,65,71,37,77,83,43,89,95,
%T A367705 49,101,107,55,113,119,61,125,131,67,137,143,73,149,155,79,161,167,85,
%U A367705 173,179,91,185,191,97,197,203,103,209,215,109,221,227,115,233,239
%N A367705 Coefficients of expansion of (1 + 5*x + 11*x^2 + 5*x^3 + 7*x^4 + x^5)/(1 - x^3)^2 in powers of x.
%C A367705 Based on an idea of _Pierre CAMI_.
%H A367705 <a href="/index/Rec#order_06">Index entries for linear recurrences with constant coefficients</a>, signature (0,0,2,0,0,-1).
%F A367705 a(n) = 3*A006369(n) + A130196(n).
%F A367705 a(n) = A007310(A006369(n) + 1).
%F A367705 a(n) = 2*a(n-3) - a(n-6) for n >= 6.
%F A367705 a(3*n) = 6*n+1, a(3*n+1) = 12*n+5, a(3*n+2) = 12*n+11.
%F A367705 Sum_{n>=0} (-1)^n/a(n) = ((2+sqrt(2))*Pi + sqrt(3)*log(7+4*sqrt(3)) + sqrt(6)*log(5-2*sqrt(6)))/12. - _Amiram Eldar_, Nov 28 2023
%t A367705 CoefficientList[Series[(1 + 5*x + 11*x^2 + 5*x^3 + 7*x^4 + x^5)/(1 - x^3)^2, {x, 0, 60}], x] (* or *)
%t A367705 LinearRecurrence[{0, 0, 2, 0, 0, -1}, {1, 5, 11, 7, 17, 23}, 60] (* _Amiram Eldar_, Nov 28 2023 *)
%Y A367705 Cf. A006369, A007310, A016921, A017581, A017653, A130196.
%K A367705 nonn,easy
%O A367705 0,2
%A A367705 _Philippe Deléham_, Nov 27 2023