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A109878 Triangle read by rows: see below. 0
1, 1, 1, 1, 2, 3, 2, 6, 12, 4, 6, 24, 60, 20, 10, 24, 120, 360, 120, 60, 36, 120, 720, 2520, 840, 420, 252, 168, 720, 5040, 20160, 6720, 3360, 2016, 1344, 960, 5040, 40320, 181440, 60480, 30240, 18144, 12096, 8640, 6480, 40320, 362880, 1814400, 604800 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,5

LINKS

Table of n, a(n) for n=1..49.

EXAMPLE

Consider the formula n! = 1*2*3...*(n-2) + 2*3*4...*(n-1)+ ...+ (n-1)*n*1*2...(n-4) + n*1*2*3*...*(n-3). E.g., 5! = 1*2*3 +2*3*4 +3*4*5 + 4*5*1 + 5*1*2.

Consider the following triangle of partition of n! based on above formula.

1

1 1

1 2 3

2 6 12 4

6 24 60 20 10

24 120 360 120 60 36

...

Sequence contains the triangle by rows.

MATHEMATICA

f[n_] := Times @@@ Sort[Partition[Range[n], n - 2, 1, {-1, -1}]]; Flatten[ Table[ f[n], {n, 2, 10}]] (* Robert G. Wilson v, Jul 13 2005 *)

CROSSREFS

Sequence in context: A188881 A143806 A276551 * A104565 A144456 A262427

Adjacent sequences:  A109875 A109876 A109877 * A109879 A109880 A109881

KEYWORD

nonn,tabl

AUTHOR

Amarnath Murthy, Jul 10 2005

EXTENSIONS

More terms from Robert G. Wilson v, Jul 18 2005

STATUS

approved

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Last modified May 29 20:42 EDT 2020. Contains 334710 sequences. (Running on oeis4.)