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 A083063 #10 Dec 07 2019 12:18:24 %S A083063 1,0,1,3,21,185,2101,29127,478297,9090909,196495641,4762874171, %T A083063 128011456717,3779594158353,121637191772461,4238682002231055, %U A083063 159023502861656433,6391554268241802725,274019342889240109297 %N A083063 a(n) = (n+1)^(n-1)/(n+2) + (-1)^n/(n+2). %o A083063 (Sage) [abs(gaussian_binomial(n,1,-(n+2))) for n in range(-1,18)] # _Zerinvary Lajos_, May 31 2009 %Y A083063 Cf. A083062, A081216, A081209. %K A083063 easy,nonn %O A083063 0,4 %A A083063 _Paul Barry_, Apr 20 2003