A100948 Irregular triangle with T(n,1) = floor(n!/3), T(n,2) = n!/2, T(n,3) = n!, read by rows.

1, 1, 2, 2, 3, 6, 8, 12, 24, 40, 60, 120, 240, 360, 720, 1680, 2520, 5040, 13440, 20160, 40320, 120960, 181440, 362880, 1209600, 1814400, 3628800

Offset

2,3

Links

Table of n, a(n) for n=2..28.

Formula

T(n,1) = A002301(n), n>=3. T(n,2) = A001710(n). T(n,3) = A000142(n).

Example

1, 1, 2;
2, 3, 6;
8, 12, 24;
40, 60, 120;
240, 360, 720;
1680, 2520, 5040;
13440, 20160, 40320;
120960, 181440, 362880;
1209600, 1814400, 3628800;

Mathematica

Flatten[Table[{If[n < 3, 1, n!/3], If[n < 2, 1, n!/2], n!}, {n, 1, 10}]]

Crossrefs

Sequence in context: A300352 A035587 A039870 * A035571 A079069 A019465

Adjacent sequences: A100945 A100946 A100947 * A100949 A100950 A100951

Keyword

nonn,tabf,easy

Author

Roger L. Bagula, Jun 07 2007

Status

approved