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 A281300 #11 Jan 20 2017 19:57:27
%S A281300 2,5,3,3,7,1,4,5,1,11,11,9,3,6,7,14,7,4,9,13,13,6,15,2,6,27,11,19,7,9,
%T A281300 3,8,17,22,34,27,23,11,2,11,9,25,15,38,17,9,21,4,6,24,16,14,28,4,30,
%U A281300 29,25,1,11,14,41,38,30,44,27,13,32,15,5,6,28,39,30
%N A281300 Triangular array read by rows: T(n, k) = (((binomial(2*p-1, p-1)-1)/p^3) mod q) + (((binomial(2*q-1, q-1)-1)/q^3) mod p), where p = prime(n) and q = prime(k) for k = 1..n-1.
%C A281300 Is p*q always a term of A228562 for T(n, k) = 0?
%C A281300 Is every term t of A228562 a term of A006881 with T(x, y) = 0, where x and y are the indices of the two prime factors of t in A000040?
%F A281300 T(n, k) = A034602(n) % prime(k) + A034602(k) % prime(n).
%e A281300 Triangle starts
%e A281300 2
%e A281300 5, 3
%e A281300 3, 7, 1
%e A281300 4, 5, 1, 11
%e A281300 11, 9, 3, 6, 7
%e A281300 14, 7, 4, 9, 13, 13
%e A281300 6, 15, 2, 6, 27, 11, 19
%e A281300 7, 9, 3, 8, 17, 22, 34, 27
%o A281300 (PARI) t(n, k) = my(p=prime(n), q=prime(k)); lift(Mod((binomial(2*q-1, q-1)-1)/q^3, p)) + lift(Mod((binomial(2*p-1, p-1)-1)/p^3, q))
%o A281300 trianglerows(n) = for(x=2, n+1, for(y=1, x-1, print1(t(x, y), ", ")); print(""))
%o A281300 trianglerows(8) \\ print initial 8 rows of triangle
%Y A281300 Cf. A034602, A228562.
%K A281300 nonn,tabl
%O A281300 1,1
%A A281300 _Felix Fröhlich_, Jan 19 2017