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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 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

LINKS

Robert Israel, Table of n, a(n) for n = 1..10000

Eric Weisstein's World of Mathematics, Triangular Number

Index to sequences related to polygonal numbers

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

Cf. A000217, A006472, A054731, A085780, A085782, A334129.

Sequence in context: A120993 A194458 A083266 * A054731 A334129 A282064

Adjacent sequences:  A334127 A334128 A334129 * A334131 A334132 A334133

KEYWORD

nonn

AUTHOR

Ilya Gutkovskiy, Apr 14 2020

STATUS

approved

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Last modified September 28 22:03 EDT 2020. Contains 337417 sequences. (Running on oeis4.)