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 A083080 #8 Sep 08 2022 08:45:10 %S A083080 1,3,33,547,11713,309411,9763393,359046339,15096500481,714852041923, %T A083080 37660464739681,2185503641764323,138548894120306881, %U A083080 9527726662032987747,706481006206076565633,56192761405186331759491 %N A083080 Main diagonal of number array A083075. %H A083080 Vincenzo Librandi, <a href="/A083080/b083080.txt">Table of n, a(n) for n = 0..300</a> %F A083080 a(n) = (n*(2n+3)^n + 1)/(n+1). %o A083080 (Magma) [(n*(2*n+3)^n+1)/(n+1): n in [0..20]]; // _Vincenzo Librandi_, Nov 12 2011 %Y A083080 Cf. A083081, A083082. %K A083080 easy,nonn %O A083080 0,2 %A A083080 _Paul Barry_, Apr 23 2003