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 A114195 #6 Jan 18 2014 06:40:59
%S A114195 1,3,1,9,8,1,27,45,13,1,81,216,106,18,1,243,945,690,192,23,1,729,3888,
%T A114195 3915,1574,303,28,1,2187,15309,20223,10941,2993,439,33,1,6561,58320,
%U A114195 97524,67788,24598,5072,600,38,1,19683,216513,446148,385560,177498
%N A114195 Riordan array (1/(1-3x),x(1-x)/(1-3x)^2).
%C A114195 Row sums are A082685. Diagonal sums are A114196.
%F A114195 T(n, k)=sum{j=0..n, C(n, j)C(j+k, 2k)2^(j-k)}; T(n, k)=sum{j=0..n-k, C(k, j)C(n+k-j, 2k)(-1)^j*3^(n-k-j)}.
%F A114195 T(n,k) = 6*T(n-1,k) + T(n-1,k-1) - 9*T(n-2,k) - T(n-2,k-1), T(0,0) = T(1,1) = 1, T(1,0) = 3, T(n,k) = 0 if k<0 or if k>n. - _Philippe Deléham_, Jan 18 2014
%e A114195 Triangle begins
%e A114195 1;
%e A114195 3, 1;
%e A114195 9, 8, 1;
%e A114195 27, 45, 13, 1;
%e A114195 81, 216, 106, 18, 1;
%e A114195 243, 945, 690, 192, 23, 1;
%K A114195 easy,nonn,tabl
%O A114195 0,2
%A A114195 _Paul Barry_, Nov 16 2005