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 A367393 #9 Nov 17 2023 09:56:01 %S A367393 1,-3,22,-194,1838,-18082,182054,-1861890,19258078,-200898626, %T A367393 2109785654,-22275498434,236225927182,-2514344180194,26845804973638, %U A367393 -287403142763522,3084015902579646,-33160937871888514,357206218412519510,-3853959574555396290,41640758821142160110 %N A367393 a(n) = A103136(2*n, n), the central terms of the inverse of the Delannoy triangle. %C A367393 A combinatorial interpretation in terms of Schroeder paths is given in A103136. %o A367393 (SageMath) # Using function A103136. %o A367393 def A367393List(size): %o A367393 M = A103136(2*size) %o A367393 return [M[2*n][n] for n in range(size)] %o A367393 print(A367393List(21)) %Y A367393 Cf. A103136. %K A367393 sign %O A367393 0,2 %A A367393 _Peter Luschny_, Nov 16 2023