OFFSET
1,2
COMMENTS
Differs from A339195 in having 77 before 66.
EXAMPLE
Triangle begins:
1
2
3 6
5 10 15 30
7 14 21 35 42 70 105 210
MATHEMATICA
nn=4;
GatherBy[SortBy[Select[Range[Times@@Prime/@Range[nn]], SquareFreeQ[#]&&PrimePi[FactorInteger[#][[-1, 1]]]<=nn&], PrimeOmega], FactorInteger[#][[-1, 1]]&]
CROSSREFS
Row lengths are A000079.
Grouping by greatest prime factor only gives A339195.
Row sums are 1 and A339360.
Partition/composition orderings: A026791, A026792, A026793, A036036, A036037, A048793, A066099, A080577, A112798, A118457, A124734, A162247, A193073, A211992, A228100, A228531, A246688, A272020, A299755, A296774, A304038, A319247, A329631, A334301, A334302, A334439, A334442, A335122, A344086, A344087, A344088, A344089.
KEYWORD
nonn,tabf
AUTHOR
Gus Wiseman, May 11 2021
STATUS
approved