%I #14 May 31 2022 15:38:16
%S 58,95,141,415,1241,2101,2951,3683,6031,7421,16531,24383,35333,39433,
%T 42001,50191,53083,66551,83981,95411,123421,146791,173951,182911,
%U 190241,229051,296321,307981,336883,409361,442583,451091,477101,500833,546883,588431,669131
%N 11-gonal (or hendecagonal) numbers which are products of two distinct primes.
%C A squarefree subsequence of 11-gonal numbers, i.e., numbers of the form k*(9*k-7)/2.
%e 58 = 4*(9*4 - 7)/2 = 2*29;
%e 141 = 6*(9*6 - 7)/2 = 3*47;
%e 415 = 10*(9*10 - 7)/2 = 5*83;
%e 3683 = 29*(9*29 - 7)/2 = 29*127.
%t Select[Table[n*(9*n - 7)/2, {n, 1, 400}], FactorInteger[#][[;; , 2]] == {1, 1} &] (* _Amiram Eldar_, May 30 2022 *)
%o (Python)
%o from sympy import factorint
%o from itertools import count, islice
%o def agen():
%o for h in (k*(9*k - 7)//2 for k in count(1)):
%o f = factorint(h, multiple=True)
%o if len(f) == len(set(f)) == 2: yield h
%o print(list(islice(agen(), 37))) # _Michael S. Branicky_, May 30 2022
%Y Intersection of A051682 and A006881.
%K nonn
%O 1,1
%A _Massimo Kofler_, May 30 2022