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 A345303 #5 Jun 28 2021 17:37:37
%S A345303 0,2,3,4,5,5,7,4,9,7,11,7,13,9,8,4,17,11,19,9,10,13,23,7,25,15,9,11,
%T A345303 29,10,31,4,14,19,12,13,37,21,16,9,41,12,43,15,14,25,47,7,49,27,20,17,
%U A345303 53,11,16,11,22,31,59,12,61,33,16,4,18,16,67,21,26,14,71,13,73,39,28
%N A345303 a(n) = Sum_{p|n, p prime} p * gcd(p,n/p).
%C A345303 If p is prime, a(p) = Sum_{p|p} p * gcd(p,p/p) = p * 1 = p.
%e A345303 a(18) = Sum_{p|18} p * gcd(p,18/p) = 2*gcd(2,9) + 3*gcd(3,6) = 2*1 + 3*3 = 11.
%t A345303 Table[Sum[k*GCD[k, n/k] (PrimePi[k] - PrimePi[k - 1]) (1 - Ceiling[n/k] + Floor[n/k]), {k, n}], {n, 100}]
%Y A345303 Cf. A345266.
%K A345303 nonn
%O A345303 1,2
%A A345303 _Wesley Ivan Hurt_, Jun 13 2021