Original entry on oeis.org
1, 4, 11, 37, 163, 907, 6067, 47107, 415027, 4084147, 44363827, 526994227, 6793931827, 94451224627, 1408352613427, 22418320792627, 379413423256627, 6802709918872627, 128803497755800627, 2568107879638168627, 53780695151756440627, 1180214324937540760627
Offset: 1
a(5) = 163 sum of row 5 terms of triangle A130478: (120 + 30 + 8 + 3 + 2); where (30, 8, 3, 2) = the first 4 reversed terms of A001048.
a(5) = 163 = 5! + A130495(4) = 120 + 43.
a(5) = 163 = 5! + (4! + 3!) + (3! + 2!) + (2! + 1!) + (1! + 1).
A130477
T(n,k) is the number of permutations of [n] with maximum descent k, T(n,k) for n >= 0 and 0 <= k <= n, triangle read by rows.
Original entry on oeis.org
1, 1, 1, 1, 2, 3, 1, 3, 8, 12, 1, 4, 15, 40, 60, 1, 5, 24, 90, 240, 360, 1, 6, 35, 168, 630, 1680, 2520, 1, 7, 48, 280, 1344, 5040, 13440, 20160, 1, 8, 63, 432, 2520, 12096, 45360, 120960, 181440, 1, 9, 80, 630, 4320, 25200, 120960, 453600, 1209600, 1814400, 1, 10, 99, 880, 6930, 47520, 277200, 1330560, 4989600, 13305600, 19958400
Offset: 0
First few rows of the triangle A130461 = (1; 1, 1; 1, 1, 1; 1, 1, 2, 1; 1, 1, 2, 3, 1; 1, 1, 2, 6, 4, 1;...). Deleting the left border and taking finite differences at the top of each remaining column, we get the first few rows of this triangle:
1;
1, 1;
1, 2, 3;
1, 3, 8, 12;
1, 4, 15, 40, 60;
1, 5, 24, 90, 240, 360;
1, 6, 35, 168, 630, 1680, 2520;
...
The triangle with each row reversed is
A092582.
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T := (n,k) -> (n-k+1+0^k)*((n+1)!/(n-k+2)!):
seq(seq(T(n,k),k=0..n),n=0..10); # Peter Luschny, Sep 17 2018
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Flatten[Table[Table[(n - k + 1 + 0^k)*(n + 1)!/(n - k + 2)!, {k,0,n}], {n, 0, 10}], 1] (* Olivier Gérard, Aug 04 2012 *)
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{T(n, k) = if( n<1 || k>n, 0, k==1, 1, n! * (n+1-k) / (n+2-k)!)}; /* Michael Somos, Jun 25 2017 */
A130460
Infinite lower triangular matrix,(1,0,0,0,...) in the main diagonal and (1,2,3,...) in the subdiagonal.
Original entry on oeis.org
1, 1, 0, 0, 2, 0, 0, 0, 3, 0, 0, 0, 0, 4, 0, 0, 0, 0, 0, 5, 0, 0, 0, 0, 0, 0, 6, 0, 0, 0, 0, 0, 0, 0, 7, 0, 0, 0, 0, 0, 0, 0, 0, 8, 0, 0, 0, 0, 0, 0, 0, 0, 0, 9, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 10, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 11, 0
Offset: 1
First few rows of the triangle:
1;
1, 0;
0, 2, 0;
0, 0, 3, 0;
0, 0, 0, 4, 0;
0, 0, 0, 0, 5, 0;
...
A130493
Triangle read by rows in which row n contains n! repeated n times.
Original entry on oeis.org
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
First few rows of the triangle:
1;
2, 2;
6, 6, 6;
24, 24, 24, 24;
...
-
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 *)
-
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
A130461
Triangle, antidiagonals of an array generated from A130460.
Original entry on oeis.org
1, 1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 2, 3, 1, 1, 1, 2, 6, 4, 1, 1, 1, 2, 6, 12, 5, 1, 1, 1, 2, 6, 24, 20, 6, 1, 1, 1, 2, 6, 24, 60, 30, 7, 1, 1, 1, 2, 6, 24, 120, 120, 42, 8, 1, 1, 1, 2, 6, 24, 120, 360, 210, 56, 9, 1, 1, 1, 2, 6, 24, 120, 720, 840, 336, 72, 10, 1, 1, 1, 2, 6, 24, 120, 720, 2520
Offset: 0
The array =
1, 1, 1, 1, 1, 1, ...
1, 1, 2, 3, 4, 5, ...
1, 1, 2, 6, 12, 20, ...
1, 1, 2, 6, 24, 60, ...
1, 1, 2, 6, 24, 120, ...
1, 1, 2, 6, 24, 120, ...
...
First few rows of the triangle:
1;
1, 1;
1, 1, 1;
1, 1, 2, 1;
1, 1, 2, 3, 1;
1, 1, 2, 6, 4, 1;
1, 1, 2, 6, 12, 5, 1;
1, 1, 2, 6, 24, 20, 6, 1;
1, 1, 2, 6, 24, 60, 30, 7, 1;
...
Original entry on oeis.org
1, 2, 3, 5, 8, 15, 28, 61, 132, 325, 790, 2133, 5680, 16501
Offset: 1
a(6) = 15 = (1 + 1 + 2 + 6 + 4 + 1), sum of row 6 terms in triangle A130461.
Showing 1-6 of 6 results.
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