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 A217473 #15 Jul 10 2025 04:13:32
%S A217473 1,4,44,1276,96976,19298224,10054374704,13714167096256,
%T A217473 48973290700730176,457851294761126415424,11206368290573330143917824,
%U A217473 718092873691648422292110244096,120467978583384630972146706659789056
%N A217473 Product of the first n+1 odd-indexed Lucas numbers A000032.
%C A217473 This sequence is used in A217472 to produce the integer instead of rational Ozeki-Prodinger triangle, and the corresponding sequence A217474.
%F A217473 a(n) = Product_{i=0..n} L(2*i+1), n >= 0, with the Lucas numbers L=A000032.
%F A217473 a(n) ~ c * phi^(n*(n+2)), where c = Product_{k>=1} (1 - 1/phi^(4*k+2)) = 0.93529381211738925891... . - _Amiram Eldar_, Jul 09 2025
%t A217473 FoldList[Times, LucasL[Range[1, 26, 2]]] (* _Amiram Eldar_, Jul 09 2025 *)
%Y A217473 Cf. A000032, A001622 (phi), 2*A070825 (product of the first n+1 Lucas numbers).
%Y A217473 Cf. A217472, A217474.
%K A217473 nonn,easy
%O A217473 0,2
%A A217473 _Wolfdieter Lang_, Oct 12 2012