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%I #25 Jun 25 2023 18:47:45
%S 207690,255255,274170,303810,304590,323610,370230,391170,426426,
%T 487578,649230,650370,744810,763230,856086,951510,1007490,1186570,
%U 1248990,1352190,1365378,1376970,1473186,1512930,1528626,1567335,1594005,1655290,1657110,1747515,1775670,1911990,1991010,2003001
%N Triangular numbers which are products of six distinct primes.
%e a(1) = T(644) = 644*(644+1)/2 = 207690 = 2*3*5*7*23*43.
%e a(2) = T(714) = 714*(714+1)/2 = 255255 = 3*5*7*11*13*17.
%e a(3) = T(740) = 740*(740+1)/2 = 274170 = 2*3*5*13*19*37.
%t Select[Accumulate[Range[2000]], FactorInteger[#][[;; , 2]] == {1, 1, 1, 1, 1, 1} &] (* _Amiram Eldar_, May 02 2023 *)
%Y Intersection of A000217 and A067885.
%K nonn
%O 1,1
%A _Massimo Kofler_, May 02 2023