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 A343713 #10 Jun 14 2021 17:31:18 %S A343713 0,0,1,0,1,0,1,2,3,0,1,3,0,1,3,4,0,1,3,6,0,1,2,3,4,5,6,7,0,1,3,6,0,1, %T A343713 3,5,6,8,0,1,3,4,6,10,0,1,3,4,6,7,9,10,0,1,2,3,6,8,10,0,1,3,6,7,8,10, %U A343713 13,0,1,3,6,10,13,0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15 %N A343713 Table read by rows: row n lists the residues of the triangular numbers modulo n. %C A343713 A117484(n) is the number of terms in row n. %e A343713 Table begins: %e A343713 row terms %e A343713 --- ----------------------------- %e A343713 1 0 %e A343713 2 0, 1 %e A343713 3 0, 1 %e A343713 4 0, 1, 2, 3 %e A343713 5 0, 1, 3 %e A343713 6 0, 1, 3, 4 %e A343713 7 0, 1, 3, 6 %e A343713 8 0, 1, 2, 3, 4, 5, 6, 7 %e A343713 9 0, 1, 3, 6 %e A343713 10 0, 1, 3, 5, 6, 8 %e A343713 11 0, 1, 3, 4, 6, 10 %e A343713 12 0, 1, 3, 4, 6, 7, 9, 10 %e A343713 13 0, 1, 2, 3, 6, 8, 10 %e A343713 14 0, 1, 3, 6, 7, 8, 10, 13 %e A343713 15 0, 1, 3, 6, 10, 13 %Y A343713 Cf. A000217, A117484. %K A343713 nonn,tabf %O A343713 1,8 %A A343713 _Jon E. Schoenfield_, May 01 2021