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A117519 Triangular numbers n divisible by the number of triangular numbers smaller than n. 0
0, 6, 15, 28, 36, 55, 105, 120, 210, 231, 378, 496, 528, 666, 990, 1540, 2145, 2556, 2628, 3081, 4095, 4186, 5460, 5565, 6105, 6555, 7140, 8128, 8256, 9316, 11628, 14706, 17955, 19900, 20100, 22155, 23436, 25200, 26565, 26796, 31878, 32131 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

The number of triangular numbers smaller than n can be found in sequence A002024 because n appears n times.

LINKS

Table of n, a(n) for n=1..42.

EXAMPLE

2145 is in the sequence because (1) it is a triangular number, (2) the number of triangular numbers smaller than 2145 is 11 and (3) 2145 is divisible by 11.

CROSSREFS

Cf. A002024, A000217.

Sequence in context: A063525 A242454 A161777 * A091012 A241988 A058008

Adjacent sequences:  A117516 A117517 A117518 * A117520 A117521 A117522

KEYWORD

nonn

AUTHOR

Luc Stevens (lms022(AT)yahoo.com), Apr 28 2006

STATUS

approved

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Last modified September 15 18:22 EDT 2019. Contains 327082 sequences. (Running on oeis4.)