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A130493
Triangle read by rows in which row n contains n! repeated n times.
4
1, 2, 2, 6, 6, 6, 24, 24, 24, 24, 120, 120, 120, 120, 120, 720, 720, 720, 720, 720, 720, 5040, 5040, 5040, 5040, 5040, 5040, 5040, 40320, 40320, 40320, 40320, 40320, 40320, 40320, 40320, 362880, 362880, 362880, 362880, 362880, 362880, 362880, 362880, 362880
OFFSET
1,2
COMMENTS
Row sums = A001563: (1, 4, 18, 96, 600, 4320, ...). A130477(n,k) * A130478(n,k) = A130493(n,k). Example: take dot products of rows with equal numbers of terms in A130477 and A130478, (1, 3, 8, 12) dot (24, 8, 3, 2) = (24, 24, 24, 24).
FORMULA
Triangle, n! repeated n times per row.
EXAMPLE
First few rows of the triangle:
1;
2, 2;
6, 6, 6;
24, 24, 24, 24;
...
MATHEMATICA
Flatten[Table[Table[n!, {n}], {n, 10}]] (* Harvey P. Dale, Dec 24 2014 *)
Table[PadRight[{}, n, n!], {n, 10}]//Flatten (* Harvey P. Dale, Jul 04 2022 *)
PROG
(Python)
from math import isqrt
from sympy import factorial
def A130493(n): return factorial((m:=isqrt(k:=n<<1))+(k>m*(m+1))) # Chai Wah Wu, Nov 07 2024
CROSSREFS
KEYWORD
nonn,tabl
AUTHOR
Gary W. Adamson, May 31 2007
EXTENSIONS
More terms from Sean A. Irvine, Jul 19 2022
STATUS
approved