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 A203166 #8 Jul 02 2013 11:14:30 %S A203166 1,3,11,50,274,394,908,2964,12576,65760,80160,174720,552960,2298240, %T A203166 11836800,13564800,28857600,90028800,370483200,1893888000,2101248000, %U A203166 4409856000,13644288000,55821312000,284083200000,308966400000 %N A203166 (n-1)-st elementary symmetric function of the first n terms of (1,2,3,4,5,1,2,3,4,5,...)=A010884. %F A203166 Conjecture: G.f. x*(1+3*x+11*x^2+50*x^3+274*x^4+154*x^5+188*x^6+324*x^7+576*x^8) / (-1+120*x^5)^2 with a(n) = 240*a(n-5) -14400*a(n-10). - _R. J. Mathar_, Jul 02 2013 %t A203166 f[k_] := 1 + Mod[k + 4, 5]; %t A203166 t[n_] := Table[f[k], {k, 1, n}] %t A203166 a[n_] := SymmetricPolynomial[n - 1, t[n]] %t A203166 Table[a[n], {n, 1, 33}] (* A203166 *) %Y A203166 Cf. A010884, A203163. %K A203166 nonn %O A203166 1,2 %A A203166 _Clark Kimberling_, Dec 30 2011