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 A327418 #8 Mar 24 2020 08:03:43 %S A327418 1,1,8255,2941884000,11957867341948125,294040106448733743008625, %T A327418 30188472144950452369737153667500, %U A327418 10143939867539251013312279527292897925000,9389957475743686923255643914812959599614184703125,21058194888200109612591474039339954750056969537259132421875 %N A327418 a(n) = A291452(2*n, n). %o A327418 (Sage) # uses[P from A327416] %o A327418 def A327418(n): return P(4, 2*n).list()[n]//factorial(n) %o A327418 print([A327418(n) for n in range(10)]) %Y A327418 Cf. A007820 (m=1), A327416 (m=2), A327417 (m=3), this sequence (m=4). %Y A327418 Associated triangles: A048993 (m=1), A156289 (m=2), A291451 (m=3), A291452 (m=4). %K A327418 nonn %O A327418 0,3 %A A327418 _Peter Luschny_, Sep 14 2019