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 A272206 #29 Jun 02 2025 12:18:07
%S A272206 1,2,2,3,4,4,5,6,7,7,8,9,10,10,11,12,12,13,14,14,15,16,16,17,18,19,19,
%T A272206 20,21,21,22,23,23,24,25,26,26,27,28,28,29,30,30,31,32,32,33,34,35,35,
%U A272206 36,37,37,38,39,39,40,41,41,42,43,43,44,45
%N A272206 Rounded barycenter of first n primes defined as a(n) = round(sum_{i=1..n}(i*prime(i)) / sum_{i=1..n}prime(i)).
%F A272206 a(n) = round(sum_{i=1..n}(i*prime(i)) / sum_{i=1..n}prime(i)).
%F A272206 a(n) = round(A014285(n)/A007504(n)).
%t A272206 a[n_] := Sum[i*Prime[i], {i, 1, n}]/Sum[Prime[i], {i, 1, n}];
%t A272206 Table[a[n] // Round, {n, 1, 64}];
%o A272206 (PARI) a(n) = round(sum(k=1, n, k*prime(k))/ sum(k=1, n, prime(k))); \\ _Michel Marcus_, May 22 2016
%Y A272206 Cf. A007504, A014285.
%K A272206 nonn
%O A272206 1,2
%A A272206 _Andres Cicuttin_, May 21 2016