A210359 Number of rows of Pascal's triangle in which the maximal number of prime factors is n.

2, 2, 4, 2, 6, 4, 7, 3, 4, 4, 12, 4, 4, 7, 7, 6, 8, 5, 9, 5, 10, 5, 10, 6, 7, 8, 6, 9, 5, 11, 4, 8, 10, 7, 5, 11, 13, 6, 10, 9, 9, 9, 9, 5, 5, 9, 12, 7, 11, 4, 15, 7, 2, 8, 12, 13, 7, 6, 13, 6, 13, 16, 7, 7, 8, 15, 9, 6, 6, 7, 4, 16, 6, 5, 20, 4, 11, 11, 6, 16

Offset

0,1

Links

Table of n, a(n) for n=0..79.

Example

As can be seen in A048273, there are 6 rows of binomial coefficients in which the maximum number of prime factors is 4: rows 10 to 15.

Mathematica

nn = 50; t = Table[0, {nn + 1}]; n = -1; f = 0; While[f < 10, n++; m = Max[Table[b = Binomial[n, k]; If[b == 1, 0, Length[FactorInteger[b]]], {k, 0, n}]]; If[0 <= m <= nn, t[[m + 1]]++; f = 0, f++]]; t

Crossrefs

Cf. A048273.

Sequence in context: A133439 A234649 A072300 * A286553 A278222 A286588

Adjacent sequences: A210356 A210357 A210358 * A210360 A210361 A210362

Keyword

nonn

Author

T. D. Noe, Apr 03 2012

Status

approved