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 A347302 #19 Aug 13 2024 13:50:54
%S A347302 0,2,7,21,69,183,669,1767,5721,17163,56529,149427,503721,1233963,
%T A347302 4422609,13988547,42326001,116887923,375168249,929468907,3253991841,
%U A347302 10227560643,31148267049,88788949947,277075307601,820517465043,2515094683929,7545284051787,22796479021761
%N A347302 a(n) = 3^n - lcm{1..n}, with a(0) = 0.
%C A347302 a(n) >= 0 [Hanson, Th. 1]
%D A347302 Hanson, Denis. "On the product of the primes." Canadian Mathematical Bulletin 15.1 (1972): 33-37.
%D A347302 Tenenbaum, G. (2015). Introduction to analytic and probabilistic number theory, 3rd ed., American Mathematical Soc. See page 14.
%H A347302 Harvey P. Dale, <a href="/A347302/b347302.txt">Table of n, a(n) for n = 0..1000</a>
%t A347302 Join[{0},Table[3^n-LCM@@Range[n],{n,30}]] (* _Harvey P. Dale_, Aug 13 2024 *)
%Y A347302 Cf. A003418, A347303.
%K A347302 nonn
%O A347302 0,2
%A A347302 _N. J. A. Sloane_, Aug 28 2021