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 A049843 #11 Jul 31 2024 09:08:30
%S A049843 1,1,2,1,1,2,1,2,1,3,1,1,3,2,2,1,2,2,2,3,2,1,1,2,3,4,2,2,1,2,3,2,1,3,
%T A049843 3,3,1,2,2,1,4,2,4,3,3,1,1,1,2,3,4,4,5,3,2,1,1,2,2,3,3,3,2,5,5,2,1,2,
%U A049843 1,2,4,2,3,2,5,4,2,2,1,1,3,1,2,2,3,3
%N A049843 Triangular array T read by rows: T(n,k)=number of nonzero remainders when Euclidean algorithm acts on primes prime(n) and prime(k), k=1,2,...,n-1; n=2,3,4,...
%e A049843 Triangle begins:
%e A049843 {1};
%e A049843 {1,2};
%e A049843 {1,1,2};
%e A049843 ...
%e A049843 T(4,3)=2 since remainders for 7=prime(4) and 5=prime(3) are 2,1,0; to wit, 7=1*5+2, 5=2*2+1, 2=2*1+0.
%Y A049843 Cf. A049816.
%K A049843 nonn,tabl
%O A049843 2,3
%A A049843 _Clark Kimberling_