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 A385439 #42 Aug 06 2025 00:55:46 %S A385439 1,2,6,10,13,14,20,42,45,44,50,78,77,70,104,136,165,152,150,182,209, %T A385439 184,172,350,325,342,322,406,365,372,400,484,561,490,582,666,665,572, %U A385439 580,820,805,860,770,930,897,846,824,1274,1325,1156 %N A385439 Row sums of triangle A385865. %o A385439 (PARI) a(n) = sum(k=1, n-1, (k^2-1) % n + 1); \\ _Michel Marcus_, Aug 01 2025 %Y A385439 Cf. A385865. %K A385439 nonn,easy %O A385439 2,2 %A A385439 _Binay Krishna Maity_, Jul 30 2025