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 A140182 #8 Jul 21 2019 17:19:33 %S A140182 1,2,3,3,7,1,4,12,4,3,5,18,10,13,1,6,25,20,35,6,3,7,33,35,75,21,19,1, %T A140182 8,42,56,140,56,70,8,3,9,52,84,238,126,196,36,25,1,10,63,120,378,252, %U A140182 462,120,117,10,3,11,75,165,570,462,966,330,405,55,31,1 %N A140182 Binomial transform of an infinite bidiagonal matrix with (1,3,1,3,1,3,...) in the main diagonal, (1,1,1,...) in the subdiagonal, the rest zeros. %C A140182 Row sums = A052940: (1, 5, 11, 23, 47, 95, ...). %F A140182 A007318 as an infinite lower triangular matrix * a bidiagonal matrix with (1,3,1,3,1,3,...) in the main diagonal, (1,1,1,...) in the subdiagonal and the rest zeros. %F A140182 From _Emeric Deutsch_, May 18 2008: (Start) %F A140182 T(n, 2k) = binomial(n+1, 2k+1); %F A140182 T(n, 2k+1) = 2*binomial(n, 2k+1) + binomial(n+1, 2k+2). (End) %e A140182 First few rows of the triangle are: %e A140182 1; %e A140182 2, 3; %e A140182 3, 7, 1; %e A140182 4, 12, 4, 3; %e A140182 5, 18, 10, 13, 1; %e A140182 6, 25, 20, 35, 6, 3; %e A140182 7, 33, 35, 75, 21, 19, 1; %e A140182 ... %p A140182 T:=proc(n,k) if `mod`(k,2)=0 then binomial(n+1,k+1) else 2*binomial(n,k)+binomial(n+1,k+1) end if end proc: for n from 0 to 10 do seq(T(n,k),k=0..n) end do; # yields sequence in triangular form - _Emeric Deutsch_, May 18 2008 %Y A140182 Cf. A052940. %K A140182 nonn,tabl %O A140182 0,2 %A A140182 _Gary W. Adamson_, May 11 2008