

A100948


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


1



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
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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



