A334130 Numbers that can be written as a product of distinct triangular numbers.

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

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