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A334130
Numbers that can be written as a product of distinct triangular numbers.
2
0, 1, 3, 6, 10, 15, 18, 21, 28, 30, 36, 45, 55, 60, 63, 66, 78, 84, 90, 91, 105, 108, 120, 126, 135, 136, 150, 153, 165, 168, 171, 180, 190, 198, 210, 216, 231, 234, 253, 270, 273, 276, 280, 300, 315, 325, 330, 351, 360, 378, 396, 406, 408, 420, 435, 450
OFFSET
1,3
MAPLE
N:= 1000: # for all terms <= N
S:= {0, 1}:
for i from 2 do
t:= i*(i+1)/2;
if t > N then break fi;
S:= S union select(`<=`, map(`*`, S, t), N)
od:
sort(convert(S, list)); # Robert Israel, Apr 21 2020
CROSSREFS
KEYWORD
nonn
AUTHOR
Ilya Gutkovskiy, Apr 14 2020
STATUS
approved