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A073329 a(n) is the n-th number to have n distinct prime factors. 6
2, 10, 60, 420, 4290, 53130, 903210, 17687670, 406816410, 11125544430, 338431883790, 11833068917670, 457077357006270, 20384767656323070, 955041577211912190, 49230430891074322890, 2740956243836856315270, 168909608387276001835590, 11054926927790884163355330 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
LINKS
David A. Corneth, Table of n, a(n) for n = 1..350 (terms <= 10^1000)
FORMULA
A001221(a(n)) = n <= A001222(a(n)). - Alois P. Heinz, Jan 09 2021
EXAMPLE
a(1) = 2 because 2 is the first number to have one prime factor.
a(2) = 10 because 10 is the second number to have two prime factors; 6 is the first.
a(3) = 60 = 2*2*3*5 because 60 is the third number to have three prime factors (2,3,5); 30 is the first and 42 is the second.
CROSSREFS
a(n) is last term in n-th row of A048692.
Sequence in context: A082042 A260657 A079856 * A290446 A350225 A277472
KEYWORD
nonn
AUTHOR
Robert G. Wilson v, Aug 22 2002
EXTENSIONS
Edited by Dean Hickerson, Nov 03 2002
More terms from Sascha Kurz, Jan 03 2003
Corrected from a(9) onwards by T. D. Noe, Dec 01 2004
More terms from David A. Corneth, Jan 09 2021
STATUS
approved

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Last modified March 18 22:56 EDT 2024. Contains 370952 sequences. (Running on oeis4.)