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 A259758 #6 Jul 20 2022 12:53:30
%S A259758 21,91,209,589,851,2881,7739,10541,16171,26069,29329,75151,95129,
%T A259758 110839,165169,194219,216409,220991,264389,374749,411601,653069,
%U A259758 717949,829931,1108969,1119311,1171741,1269139,1416689,2059789,3161729,3374249,3428459,4924109
%N A259758 Squarefree semiprimes of the form (2*p - 3) * (3*p - 2), p prime.
%C A259758 a(n) = (2*A259730(n) - 3) * (3*A259730(n) - 2);
%C A259758 3431 = A033569(24) = (2*25-3)*(3*25-2) = 47*73 = A006881(946) is the smallest term in the intersection of A006881 and A033569 not belonging to this sequence.
%H A259758 Reinhard Zumkeller, <a href="/A259758/b259758.txt">Table of n, a(n) for n = 1..10000</a>
%F A259758 a(n) = 6*A259730(n)^2 - 13*A259730(n) + 6.
%e A259758 . n | p = A259730(n) | 2*p - 3 | 3*p - 2 | a(n)
%e A259758 . ----+----------------+---------+---------+--------
%e A259758 . 1 | 3 | 3 | 7 | 21
%e A259758 . 2 | 5 | 7 | 13 | 91
%e A259758 . 3 | 7 | 11 | 19 | 209
%e A259758 . 4 | 11 | 19 | 31 | 589
%e A259758 . 5 | 13 | 23 | 37 | 851
%e A259758 . 6 | 23 | 43 | 67 | 2881
%e A259758 . 7 | 37 | 71 | 109 | 7739
%e A259758 . 8 | 43 | 83 | 127 | 10541
%e A259758 . 9 | 53 | 103 | 157 | 16171
%e A259758 . 10 | 67 | 131 | 199 | 26069
%e A259758 . 11 | 71 | 139 | 211 | 29329
%e A259758 . 12 | 113 | 223 | 337 | 75151 .
%t A259758 Select[Table[(2p-3)(3p-2),{p,Prime[Range[200]]}],PrimeOmega[#]==2&&SquareFreeQ[ #]&] (* _Harvey P. Dale_, Jul 20 2022 *)
%o A259758 (Haskell)
%o A259758 a259758 n = (2 * p - 3) * (3 * p - 2) where p = a259730 n
%Y A259758 Cf. A259730, subsequence of A006881, subsequence of A033569.
%K A259758 nonn
%O A259758 1,1
%A A259758 _Reinhard Zumkeller_, Jul 05 2015