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 A046583 #9 Jul 02 2025 16:01:57 %S A046583 1,1,1,1,5,1,1,9,1,1,19,13,1,1,1,8,17,1,1,2,35,49,21,1,1,119,2,35,25, %T A046583 1,1,259,189,95,29,1,1,1,112,1,71,1,31,33,1,1,2,483,1,183,1,102,157, %U A046583 37,1,1,2,849,1,285,565,2,97,41,1,1,2,1815,2,1419,1705,759,235,45,1,1,1 %N A046583 First denominator and then numerator of each element to the right of the central elements of the 1/4-Pascal triangle (by row), excluding 4's. %e A046583 1/1; 1/1 1/1; 1/1 1/4 1/1; 1/1 5/4 5/4 1/1; 1/1 9/4 5/2 9/4 1/1; 1/1 13/4 19/4 19/4 13/4 1/1; 1/1 17/4 8/1 19/2 8/1 17/4 1/1; 1/1 21/4 49/4 35/2 35/2 49/4 21/4 1/1; ... %Y A046583 Cf. A046563. %K A046583 nonn %O A046583 1,5 %A A046583 _Mohammad K. Azarian_ %E A046583 More terms from _James Sellers_, Dec 14 1999