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 A083073 #5 Mar 04 2018 21:19:29 %S A083073 1,5,41,439,5741,88889,1594405,32574371,747753161,19071735493, %T A083073 535461077009,16419373641455,546208347402901,19598084579455217, %U A083073 754617425461612781,31043368421052631579,1359040255729886061905 %N A083073 A subdiagonal of number array A083064. %F A083073 a(n) = ((n+3)*(n+5)^n + 1)/(n+4). %Y A083073 Cf. A083072, A083071, A083069. %K A083073 easy,nonn %O A083073 0,2 %A A083073 _Paul Barry_, Apr 21 2003