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A362758
Triangular numbers which are products of six distinct primes.
0
207690, 255255, 274170, 303810, 304590, 323610, 370230, 391170, 426426, 487578, 649230, 650370, 744810, 763230, 856086, 951510, 1007490, 1186570, 1248990, 1352190, 1365378, 1376970, 1473186, 1512930, 1528626, 1567335, 1594005, 1655290, 1657110, 1747515, 1775670, 1911990, 1991010, 2003001
OFFSET
1,1
EXAMPLE
a(1) = T(644) = 644*(644+1)/2 = 207690 = 2*3*5*7*23*43.
a(2) = T(714) = 714*(714+1)/2 = 255255 = 3*5*7*11*13*17.
a(3) = T(740) = 740*(740+1)/2 = 274170 = 2*3*5*13*19*37.
MATHEMATICA
Select[Accumulate[Range[2000]], FactorInteger[#][[;; , 2]] == {1, 1, 1, 1, 1, 1} &] (* Amiram Eldar, May 02 2023 *)
CROSSREFS
Intersection of A000217 and A067885.
Sequence in context: A178285 A101701 A092011 * A216900 A072679 A147705
KEYWORD
nonn
AUTHOR
Massimo Kofler, May 02 2023
STATUS
approved