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 A228186 #202 Oct 30 2020 13:37:53 %S A228186 4,9,18,29,44,61,81,104,130,159,191,226,263,304,347,393,442,494,549, %T A228186 607,667,731,797,866,938,1013,1091,1172,1256,1342,1432,1524,1619,1717, %U A228186 1818,1922,2029,2139,2251,2367,2485,2606,2730,2857,2987,3120,3255,3394,3535 %N A228186 a(n) is the smallest natural number k such that (k+n+1)!*(k-n-2)! < 2*k!*(k-1)!. %H A228186 John Ting, <a href="/A228186/b228186.txt">Table of n, a(n) for n = 0..100.</a> %o A228186 (PARI) for(n=0,50,for(k=n+2,oo,if(((k+n+1)!)*((k-n-2)!) < 2* (k!)* ((k-1)!),print1(k,", ");break))) \\ _Hugo Pfoertner_, Oct 30 2020 using _Adam P. Goucher_'s definition %Y A228186 Cf. A100967. %K A228186 nonn %O A228186 0,1 %A A228186 _John Ting_, Aug 15 2013 %E A228186 Entry revised by _N. J. A. Sloane_, Oct 30 2020, incorporating a more precise definition from _Adam P. Goucher_