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A076579
Triangular numbers which are 5-almost primes.
0
120, 300, 378, 496, 630, 780, 990, 1128, 1485, 1540, 1596, 2556, 2628, 2850, 3160, 3321, 3570, 3828, 4095, 4851, 5778, 5886, 6328, 6786, 7750, 8778, 9045, 9870, 10878, 11781, 12090, 13203, 13530, 14028, 14535, 14706, 15225, 16110, 16290
OFFSET
1,1
EXAMPLE
a(1)=120, 120 is a triangular number and 120=2*2*2*3*5 i.e. is a product of 5 prime factors so is 5-almost prime.
CROSSREFS
Sequence in context: A211467 A257712 A250607 * A345350 A121898 A048190
KEYWORD
base,easy,nonn
AUTHOR
Shyam Sunder Gupta, Oct 19 2002
STATUS
approved