A116853 Difference triangle of factorial numbers read by upward diagonals.

1, 1, 2, 3, 4, 6, 11, 14, 18, 24, 53, 64, 78, 96, 120, 309, 362, 426, 504, 600, 720, 2119, 2428, 2790, 3216, 3720, 4320, 5040, 16687, 18806, 21234, 24024, 27240, 30960, 35280, 40320

Offset

1,3

Comments

This is a subsequence of Euler's difference table A068106 and of A047920 (in a different ordering), since 0! = 1 was left out here. - Georg Fischer, Mar 23 2019

Links

Reinhard Zumkeller, Rows n = 1..125 of triangle, flattened

Formula

Take successive difference rows of factorial numbers n! starting with n=1. Reorient into a triangle format.

Example

Starting with 1, 2, 6, 24, 120 ... we take the first difference row (A001563), second, third, etc. Reorient into a flush left format, getting:
[1]    1;
[2]    1,   2;
[3]    3,   4,   6;
[4]   11,  14,  18,  24;
[5]   53,  64,  78,  96, 120;
[6]  309, 362, 426, 504, 600, 720;
...

Mathematica

rows = 8;
rr = Range[rows]!;
dd = Table[Differences[rr, n], {n, 0, rows-1}];
T = Array[t, {rows, rows}];
Do[Thread[Evaluate[Diagonal[T, -k+1]] = dd[[k, ;; rows-k+1]]], {k, rows}];
Table[t[n, k], {n, 1, rows}, {k, 1, n}] // Flatten (* Jean-François Alcover, Dec 21 2019 *)

Prog

(Haskell)
a116853 n k = a116853_tabl !! (n-1) !! (k-1)
a116853_row n = a116853_tabl !! (n-1)
a116853_tabl = map reverse $ f (tail a000142_list) [] where
   f (u:us) vs = ws : f us ws where ws = scanl (-) u vs
-- Reinhard Zumkeller, Aug 31 2014

Crossrefs

Cf. A000142 (factorial numbers).

Cf. A000255 (first column and inverse binomial transform of A000142).

N-th forward differences of A000142: A001563 (1st), A001564 (2nd), A001565 (3rd), A001688 (4th), A001689 (5th).

Cf. A047920 (with 0!, different order), A068106 (with 0!), A180191 (row sums), A246606 (central terms).

Sequence in context: A050886 A341652 A079310 * A342334 A066615 A133951

Adjacent sequences: A116850 A116851 A116852 * A116854 A116855 A116856

Keyword

nonn,tabl

Author

Gary W. Adamson, Feb 24 2006

Status

approved