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 A342480 #8 Mar 14 2021 05:14:38
%S A342480 1,6,10,15,1155,1365,12155,1616615,37182145,11849255,33426748355,
%T A342480 247357937827,10141675450907,25652473199353,2928046583754721,
%U A342480 155186468939000213,223317113839049087,558516101711461766587,796182527971658263007,241532826894674874877669,430046252763689411367557
%N A342480 a(n) is the denominator of the asymptotic density of numbers whose second smallest prime divisor (A119288) is prime(n).
%C A342480 See A342479 for details.
%H A342480 Amiram Eldar, <a href="/A342480/b342480.txt">Table of n, a(n) for n = 1..376</a>
%t A342480 f[n_] := Module[{p = Prime[n], q}, q = Select[Range[p - 1], PrimeQ]; Plus @@ (1/(q - 1))*Times @@ ((q - 1)/q)/p]; Denominator @ Array[f, 30]
%Y A342480 Cf. A038110, A038111, A119288, A342479 (numerators).
%K A342480 nonn,easy,frac
%O A342480 1,2
%A A342480 _Amiram Eldar_, Mar 13 2021