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 A359845 #9 Jan 28 2023 18:25:59
%S A359845 9010,20710,39610,67735,91885,108946,163846,191710,197110,237010,
%T A359845 243010,293710,307135,342010,349210,409510,461206,466210,474610,
%U A359845 488206,526585,544510,619210,625006,640594,656374,678385,688510,698710,708985,789526,890506,934966,985366,992674,1039585
%N A359845 Centered triangular numbers which are products of four distinct primes.
%C A359845 A squarefree subsequence of centered triangular numbers.
%e A359845 9010 = 2 * 5 * 17 * 53 = (3 * 78 * (78 - 1) / 2) + 1.
%e A359845 20710 = 2 * 5 * 19 * 109 = (3 * 118 * (118 - 1) / 2) + 1.
%e A359845 39610 = 2 * 5 * 17 * 233 = (3 * 163 * (163 - 1) / 2) + 1.
%t A359845 Select[Table[3*n*(n - 1)/2 + 1, {n, 1, 1000}], FactorInteger[#][[;; , 2]] == {1, 1, 1, 1} &] (* _Amiram Eldar_, Jan 15 2023 *)
%Y A359845 Intersection of A005448 and A046386.
%K A359845 nonn
%O A359845 1,1
%A A359845 _Massimo Kofler_, Jan 15 2023