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 A360667 #12 Feb 16 2023 11:59:04 %S A360667 1,1,1,2,4,2,10,30,30,10,64,256,384,256,64,462,2310,4620,4620,2310, %T A360667 462,3584,21504,53760,71680,53760,21504,3584,29172,204204,612612, %U A360667 1021020,1021020,612612,204204,29172,245760,1966080,6881280,13762560,17203200,13762560,6881280,1966080,245760 %N A360667 Triangle read by rows: T(n,m)=4^(n-1)*C(n,m)*C(3*n/2-2,n-1)/n, for 0 <= m <= n, with T(0,0)=1. %F A360667 G.f.: sin(arcsin(216*x^2*(y+1)^2-1)/3)/6+13/12. %F A360667 G.f.: 1+x*(sqrt(3)/2)*(sech(arccosh(-sqrt(108)*x*(1+y))/3))*(1+y). %e A360667 Triangle T(n, m) starts: %e A360667 [0] 1; %e A360667 [1] 1, 1; %e A360667 [2] 2, 4, 2; %e A360667 [3] 10, 30, 30, 10; %e A360667 [4] 64, 256, 384, 256, 64; %e A360667 [5] 462, 2310, 4620, 4620, 2310, 462; %e A360667 [6] 3584, 21504, 53760, 71680, 53760, 21504, 3584; %e A360667 [7] 29172, 204204, 612612, 1021020,1021020, 612612, 204204, 29172; %t A360667 T[0, 0] = 1; %t A360667 T[n_, m_] := 4^(n-1)*Binomial[n, m]*Binomial[3n/2-2, n-1]/n; %t A360667 Table[T[n, m], {n, 0, 10}, {m, 0, n}] // Flatten (* _Jean-François Alcover_, Feb 16 2023 *) %o A360667 (Maxima) %o A360667 T(n,m):=if n=0 and m=0 then 1 else if n=0 then 0 else (4^(n-1)*binomial(n,m)*binomial((3*n)/2-2,n-1))/(n); %Y A360667 Cf. A078531. %K A360667 nonn,tabl %O A360667 0,4 %A A360667 _Vladimir Kruchinin_, Feb 16 2023