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A292922
Triangle read by rows: T(n,k) is the number of numbers <= primorial(n) with k prime factors, counted without multiplicity.
0
1, 4, 1, 16, 12, 1, 60, 116, 32, 1, 377, 1085, 745, 101, 1, 3323, 11172, 11534, 3735, 264, 1, 42518, 153752, 195801, 99914, 17808, 715, 1, 646580, 2464246, 3535748, 2314475, 667138, 69877, 1624, 1, 12285485, 48959467
OFFSET
1,2
EXAMPLE
The triangle T(n, m) begins:
n\k 1 2 3 4 5 6
1: 1
2: 4 1
3: 16 12 1
4: 60 116 32 1
5: 377 1085 745 101 1
6: 3323 11172 11534 3735 264 1
PROG
(PARI) a(n) = r=prod(i=1, n, prime(i)); for(s=1, n, k=sum(t=2, r, omega(t)==s) ; k)
CROSSREFS
Cf. A001221.
Sequence in context: A272279 A271413 A271262 * A117438 A075499 A367022
KEYWORD
nonn,tabl
AUTHOR
Gionata Neri, Sep 26 2017
STATUS
approved