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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

%I #9 Jun 23 2017 21:24:23

%S 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,

%T 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,

%U 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

%N Triangle: number of distinct prime factors in n-th primorial numbers when n prime factors first appears and in n-1 subsequent integers after.

%C 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.

%e n-th row of table consists of n numbers A001221[A002110(n+j)], j=0...n-1:

%e 1,

%e 2,1,

%e 3,1,1,

%e 4,1,2,2,

%e 5,1,2,2,3,

%e 6,2,2,3,2,2,

%e 7,3,2,3,3,2,4,

%e 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.

%t 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]

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

%K nonn,tabl

%O 1,2

%A _Labos Elemer_, May 27 2003

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Last modified April 25 04:42 EDT 2024. Contains 371964 sequences. (Running on oeis4.)