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 A326997 #3 Aug 13 2019 05:24:30 %S A326997 1,2,4,8,19,75,866,38546,6435801,4411898775,12497557933746, %T A326997 172551409850674506,10689931902245247171663, %U A326997 3609784804719064481553949028,6092547417568499138450938430843772,57094466457110460366185443558858325798634 %N A326997 Antidiagonal sums of A327001. %p A326997 seq(add(A327001(n-k, k), k=0..n), n=0..15); %K A326997 nonn %O A326997 0,2 %A A326997 _Peter Luschny_, Aug 13 2019