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A132896 Triangle read by rows: T(n,k)=number of prime divisors of C(n,k), counted with multiplicity (0<=k<=n). 3
0, 0, 0, 0, 1, 0, 0, 1, 1, 0, 0, 2, 2, 2, 0, 0, 1, 2, 2, 1, 0, 0, 2, 2, 3, 2, 2, 0, 0, 1, 2, 2, 2, 2, 1, 0, 0, 3, 3, 4, 3, 4, 3, 3, 0, 0, 2, 4, 4, 4, 4, 4, 4, 2, 0, 0, 2, 3, 5, 4, 5, 4, 5, 3, 2, 0, 0, 1, 2, 3, 4, 4, 4, 4, 3, 2, 1, 0, 0, 3, 3, 4, 4, 6, 5, 6, 4, 4, 3, 3, 0 (list; table; graph; refs; listen; history; text; internal format)
OFFSET
0,12
LINKS
FORMULA
T(n, k) = A001222(A007318(n, k)). - Michel Marcus, Nov 04 2020
EXAMPLE
T(8,3)=4 because C(8,3)=56=2*2*2*7.
Triangle begins:
0;
0,0;
0,1,0;
0,1,1,0;
0,2,2,2,0;
0,1,2,2,1,0;
MAPLE
with(numtheory): T:=proc(n, k) if k <= n then bigomega(binomial(n, k)) else x end if end proc: for n from 0 to 12 do seq(T(n, k), k=0..n) end do; # yields sequence in triangular form
CROSSREFS
Cf. A048571, which counts only distinct factors.
Sequence in context: A123186 A127323 A327298 * A089789 A257921 A261119
KEYWORD
nonn,tabl
AUTHOR
Emeric Deutsch, Oct 16 2007
STATUS
approved

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Last modified April 24 08:59 EDT 2024. Contains 371935 sequences. (Running on oeis4.)