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A076581
Triangular numbers which are 7-almost primes.
0
2080, 4560, 8128, 9180, 10296, 10440, 12720, 12880, 15400, 18336, 18528, 21528, 23220, 23436, 29403, 29646, 37128, 39060, 43956, 52326, 56280, 61425, 64980, 67896, 70500, 81810, 82215, 86320, 86736, 93096, 93528, 100576, 103740, 105570
OFFSET
1,1
EXAMPLE
a(1)=2080, 2080 is a triangular number and 2080=2*2*2*2*2*5*13 i.e. is a product of 7 prime factors so is 7-almost prime.
CROSSREFS
Sequence in context: A249654 A180921 A270537 * A183675 A178272 A194605
KEYWORD
base,easy,nonn
AUTHOR
Shyam Sunder Gupta, Oct 19 2002
STATUS
approved