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 A202395 #6 Feb 22 2013 14:40:24 %S A202395 1,1,1,2,4,2,5,13,11,3,13,40,46,24,5,34,120,172,128,50,8,89,354,603, %T A202395 572,319,98,13,233,1031,2025,2311,1651,733,187,21,610,2972,6592,8740, %U A202395 7548,4324,1600,348,34 %N A202395 Triangle T(n,k), read by rows, given by (1, 1, 1, 0, 0, 0, 0, 0, 0, 0, ...) DELTA (1, 1, -1, 0, 0, 0, 0, 0, 0, 0, ...) where DELTA is the operator defined in A084938. %C A202395 T(n,n) = Fibonacci(n+1) = A000045(n+1). %F A202395 T(n,k) = 3*T(n-1,k) + T(n-1,k-1) + T(n-2,k-2) - T(n-2,k) with T(0,0) = T(1,0) = T(1,1) = 1 and T(n,k) = 0 if k<0 or if n<k. %F A202395 G.f.: (1-2*x)/(1-(3+y)*x+(1-y^2)*x^2). %F A202395 Sum_{k, 0<=k<=n} T(n,k)*x^k = A000007(n), A001519(n), A081294(n), A180036(n) for x = -1, 0, 1, 2 respectively. %e A202395 Triangle begins : %e A202395 1 %e A202395 1, 1 %e A202395 2, 4, 2 %e A202395 5, 13, 11, 3 %e A202395 13, 40, 46, 24, 5 %e A202395 34, 120, 172, 128, 50, 8 %e A202395 89, 354, 603, 572, 319, 98, 13 %Y A202395 Cf. A000045, A001519, A123585, A202389, A202390, %K A202395 nonn,tabl %O A202395 0,4 %A A202395 _Philippe Deléham_, Dec 18 2011