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A076580 Triangular numbers which are 6-almost primes. 1
528, 1176, 4656, 4950, 5460, 6216, 7140, 7260, 7875, 11628, 13041, 14196, 15576, 17766, 17955, 19110, 20100, 21736, 24976, 26796, 28680, 28920, 31878, 33930, 34980, 37950, 44850, 45150, 46056, 46360, 49770, 56616, 58653, 58996, 59340 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Harvey P. Dale, Table of n, a(n) for n = 1..1000

EXAMPLE

a(1)=528, 528 is a triangular number and 528=2*2*2*2*3*11 i.e. is a product of 6 prime factors so is 6-almost prime.

MATHEMATICA

Select[Accumulate[Range[400]], PrimeOmega[#]==6&] (* Harvey P. Dale, May 19 2019 *)

CROSSREFS

Sequence in context: A085329 A157475 A158365 * A304512 A037944 A282096

Adjacent sequences:  A076577 A076578 A076579 * A076581 A076582 A076583

KEYWORD

base,easy,nonn

AUTHOR

Shyam Sunder Gupta, Oct 19 2002

STATUS

approved

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Last modified May 19 05:04 EDT 2022. Contains 353826 sequences. (Running on oeis4.)