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A084296 Triangle: number of distinct prime factors in n-th primorial numbers when n prime factors first appears and in n-1 subsequent integers after. 0
1, 2, 1, 3, 1, 1, 4, 1, 2, 2, 5, 1, 2, 2, 3, 6, 2, 2, 3, 2, 2, 7, 3, 2, 3, 3, 2, 4, 8, 2, 3, 2, 4, 2, 3, 2, 9, 2, 3, 3, 3, 2, 4, 3, 4, 10, 3, 3, 2, 2, 2, 4, 3, 3, 2, 11, 1, 4, 3, 2, 4, 5, 4, 3, 3, 4, 12, 3, 3, 4, 2, 3, 6, 2, 3, 5, 4, 3, 13, 3, 4, 2, 3, 3, 3, 3, 3, 3, 6, 2, 4, 14, 2, 3, 2, 4, 5, 4, 5, 3, 3, 6, 4 (list; table; graph; refs; listen; history; internal format)
OFFSET

1,2

COMMENTS

Omega-values(=A001221) in the subsequent neighborhood of radius n, for primorial numbers are usually neither all distinct or all equal items as it is required in A068069, A045983 sequences.

EXAMPLE

n-th row of table consists of n numbers A001221[A02110(n+j)], j=0...n-1:

1,

2,1,

3,1,1,

4,1,2,2,

5,1,2,2,3,

6,2,2,3,2,2,

7,3,2,3,3,2,4,

Rows starts with n at indices which are central polygonal numbers:a[A000124(n)]=n; rows ends at a[A000217(n)] terms, at triangular number indices.

MATHEMATICA

lf[x_] := Length[FactorInteger[x]] q[x_] := Apply[Times, Table[Prime[w], {w, 1, x}]] Flatten[Table[Table[lf[q[n]+j], {j, 0, n-1}], {n, 1, 20}], 1]

CROSSREFS

Cf. A001221, A002110, A068069, A045983, A000217, A000124.

Sequence in context: A113924 A178340 A173261 * A062534 A143349 A182715

Adjacent sequences:  A084293 A084294 A084295 * A084297 A084298 A084299

KEYWORD

nonn,tabl

AUTHOR

Labos E. (labos(AT)ana.sote.hu), May 27 2003

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Last modified February 17 11:35 EST 2012. Contains 206011 sequences.