cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

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A248814 a(n) = (6n)!/(6!^n).

Original entry on oeis.org

1, 1, 924, 17153136, 2308743493056, 1370874167589326400, 2670177736637149247308800, 14007180988362844601443040716800, 171889289584866507880743491472699801600, 4439413043841128802009762476941510771390464000
Offset: 0

Views

Author

Tilman Piesk, Oct 29 2014

Keywords

Comments

Column 6 of A187783.
Number of permutations of a multiset that contains n different elements, each occurring 6 times.

Examples

			a(3) = (6*3)!/(6!^3) = 17153136 is the number of permutations of a multiset that contains 3 different elements 6 times, e.g., {1,1,1,1,1,1,2,2,2,2,2,2,3,3,3,3,3,3}.
		

Crossrefs

Cf. A187783.

Programs

Formula

a(n) = (6n)!/(6!^n).

A172603 a(n) = (7n)!/(7!^n).

Original entry on oeis.org

1, 1, 3432, 399072960, 472518347558400, 3177459078523411968000, 85722533226982363751829504000, 7363615666157189603982585462030336000, 1707750599894443404262670865631874246246400000
Offset: 0

Views

Author

R. H. Hardin, Feb 06 2010

Keywords

Comments

From Tilman Piesk, Oct 30 2014: (Start)
Column 7 of A187783.
Number of permutations of a multiset that contains n different elements 7 times.
Or in other words (the former title of this sequence):
Number of 7*n X n 0..1 arrays with row sums 1 and column sums 7.
(End)

Examples

			a(3) = (7*3)!/(7!^3) = 399072960 is the number of permutations of a multiset that contains 3 different elements 7 times, e.g., {1,1,1,1,1,1,1,2,2,2,2,2,2,2,3,3,3,3,3,3,3}.
		

Programs

Formula

a(n) = (7n)!/(7!^n).

Extensions

Name changed by Tilman Piesk, Oct 30 2014

A172609 a(n) = (8n)!/(8!^n).

Original entry on oeis.org

1, 1, 12870, 9465511770, 99561092450391000, 7656714453153197981835000, 2889253496242619386328267523990000, 4104167472585675600759440022842715359250000, 18165723931630806756964027928179555634194028454000000
Offset: 0

Views

Author

R. H. Hardin, Feb 06 2010

Keywords

Comments

From Tilman Piesk, Oct 30 2014: (Start)
Column 8 of A187783.
Number of permutations of a multiset that contains n different elements, each occurring 8 times.
Or in other words (the former title of this sequence):
Number of 8*n X n 0..1 arrays with row sums 1 and column sums 8.
(End)

Examples

			a(3) = (8*3)!/(8!^3) = 9465511770 is the number of permutations of a multiset that contains 3 different elements 8 times, e.g., {1,1,1,1,1,1,1,1,2,2,2,2,2,2,2,2,3,3,3,3,3,3,3,3}.
		

Programs

Formula

a(n) = (8n)!/(8!^n).

Extensions

Name changed by Tilman Piesk, Oct 30 2014

A172613 a(n) = (9n)!/(9!^n).

Original entry on oeis.org

1, 1, 48620, 227873431500, 21452752266265320000, 19010638202652030712978200000, 101097362223624462291180422369532000000, 2392741010223442438553822446842770682716580000000, 203653377853981828616656775313699668953042169048889600000000
Offset: 0

Views

Author

R. H. Hardin, Feb 06 2010

Keywords

Comments

From Tilman Piesk, Oct 30 2014: (Start)
Column 9 of A187783.
Number of permutations of a multiset that contains n different elements, each occurring 9 times.
Or in other words (the former title of this sequence):
Number of 9*n X n 0..1 arrays with row sums 1 and column sums 9.
(End)

Examples

			a(3) = (9*3)!/(9!^3) = 227873431500 is the number of permutations of a multiset that contains 3 different elements, each occurring 9 times, e.g., {1,1,1,1,1,1,1,1,1,2,2,2,2,2,2,2,2,2,3,3,3,3,3,3,3,3,3}.
		

Programs

Formula

a(n) = (9n)!/(9!^n).

Extensions

Name changed by Tilman Piesk, Oct 30 2014

A347811 Number A(n,k) of k-dimensional lattice walks from {n}^k to {0}^k using steps that decrease the Euclidean distance to the origin and that change each coordinate by at most 1; square array A(n,k), n>=0, k>=0, read by antidiagonals.

Original entry on oeis.org

1, 1, 1, 1, 1, 1, 1, 3, 1, 1, 1, 19, 25, 1, 1, 1, 323, 211075, 241, 1, 1, 1, 38716, 1322634996717, 2062017739, 2545, 1, 1, 1, 32253681, 16042961630858858915656, 29261778984922904560001, 32191353922714, 28203, 1, 1
Offset: 0

Views

Author

Alois P. Heinz, Sep 14 2021

Keywords

Comments

Lattice points may have negative coordinates, and different walks may differ in length. All walks are self-avoiding.

Examples

			Square array A(n,k) begins:
  1, 1,     1,              1,                       1,     1, ...
  1, 1,     3,             19,                     323, 38716, ...
  1, 1,    25,         211075,           1322634996717, ...
  1, 1,   241,     2062017739, 29261778984922904560001, ...
  1, 1,  2545, 32191353922714, ...
  1, 1, 28203, ...
  ...
		

Crossrefs

Columns k=0+1, 2-3 give: A000012, A346539, A347813.
Rows n=0-2 give: A000012, A346840, A347812.
Main diagonal gives A347810.

Programs

  • Maple
    s:= proc(n) option remember;
         `if`(n=0, [[]], map(x-> seq([x[], i], i=-1..1), s(n-1)))
        end:
    b:= proc(l) option remember; (n-> `if`(l=[0$n], 1, add((h-> `if`(
          add(i^2, i=h) b([n$k]):
    seq(seq(A(n, d-n), n=0..d), d=0..8);
  • Mathematica
    s[n_] := s[n] = If[n == 0, {{}}, Sequence @@ Table[Append[#, i], {i, -1, 1}]& /@ s[n-1]];
    b[l_List] := b[l] = With[{n = Length[l]}, If[l == Table[0, {n}], 1, Sum[With[{h = l+x}, If[h.h < l.l, b[Sort[h]], 0]], {x, s[n]}]]];
    A[n_, k_] := b[Table[n, {k}]];
    Table[Table[A[n, d-n], {n, 0, d}], {d, 0, 8}] // Flatten (* Jean-François Alcover, Nov 03 2021, after Alois P. Heinz *)

A120666 Triangle read by rows: T(n, k) = (n*k)!/(n!)^k.

Original entry on oeis.org

1, 1, 6, 1, 20, 1680, 1, 70, 34650, 63063000, 1, 252, 756756, 11732745024, 623360743125120, 1, 924, 17153136, 2308743493056, 1370874167589326400, 2670177736637149247308800, 1, 3432, 399072960, 472518347558400, 3177459078523411968000, 85722533226982363751829504000, 7363615666157189603982585462030336000
Offset: 1

Views

Author

Roger L. Bagula, Aug 11 2006

Keywords

Comments

T(m,n) is the number of ways to distribute n*m different toys among m different kids so that each kid gets exactly n toys. For example, with n=3 and m=2, the 6 different toys, t1, t2, t3, t4, t5 and t6, can be distributed in exactly 20 ways among the 2 kids, k1 and k2, since there are C(6,3)=20 ways to choose the three toys for k1, with the other three toys going to k2. The proof for the general case is based on the identity C(n*m,n)*C(n*m-n,n)*...*C(n*m-n*(m-1),n) = (n*m)!/(n!)^m. - Dennis P. Walsh, Apr 12 2018

Examples

			Triangle begins:
  1;
  1,   6;
  1,  20,   1680;
  1,  70,  34650,    63063000;
  1, 252, 756756, 11732745024, 623360743125120;
		

Crossrefs

Programs

  • Magma
    [Factorial(n*k)/(Factorial(n))^k: k in [1..n], n in [1..10]]; // G. C. Greubel, Dec 26 2022
    
  • Maple
    T:= (m, n)-> (n*m)!/(m!)^n:
    seq(seq(T(m, n), n=1..m), m=1..7);  # Alois P. Heinz, Apr 12 2018
  • Mathematica
    Table[(n*k)!/(n!)^k, {n,10}, {k,n}]//Flatten
  • SageMath
    def A120666(n,k): return gamma(n*k+1)/(factorial(n))^k
    flatten([[A120666(n,k) for k in range(1,n+1)] for n in range(1,11)]) # G. C. Greubel, Dec 26 2022

Formula

T(n, k) = (k*n)!/(n!)^k.

Extensions

Edited by N. J. A. Sloane, Jun 17 2007
Offset corrected by Alois P. Heinz, Apr 12 2018
New name using formula by Joerg Arndt, Apr 15 2018

A141906 Triangle t(n,m) = (n*m)!/(m!^n) read by rows, 0<=m<=n.

Original entry on oeis.org

1, 1, 1, 1, 2, 6, 1, 6, 90, 1680, 1, 24, 2520, 369600, 63063000, 1, 120, 113400, 168168000, 305540235000, 623360743125120, 1, 720, 7484400, 137225088000, 3246670537110000, 88832646059788350720, 2670177736637149247308800
Offset: 0

Views

Author

Roger L. Bagula and Gary W. Adamson, Sep 14 2008

Keywords

Comments

Row sums are in A221177.

Examples

			1;
1, 1;
1, 2, 6;
1, 6, 90, 1680;
1, 24, 2520, 369600, 63063000;
1, 120, 113400, 168168000, 305540235000, 623360743125120;
1, 720, 7484400, 137225088000, 3246670537110000, 88832646059788350720, 2670177736637149247308800;
		

Crossrefs

Programs

  • Maple
    A141906 := proc(n,m)
            (n*m)!/m!^n ;
    end proc:
    seq(seq(A141906(n,m),m=0..n),n=0..5) ; # R. J. Mathar, Nov 08 2011
  • Mathematica
    Clear[t, n, m]; t[n_, m_] = (n*m)!/m!^n; Table[Table[t[n, m], {m, 0, n}], {n, 0, 10}]; Flatten[%]

A375694 Number A(n,k) of multiset permutations of {{1}^k, {2}^k, ..., {n}^k} with no fixed k-tuple {j}^k; square array A(n,k), n>=0, k>=0, read by antidiagonals.

Original entry on oeis.org

1, 1, 0, 1, 0, 0, 1, 0, 1, 0, 1, 0, 5, 2, 0, 1, 0, 19, 74, 9, 0, 1, 0, 69, 1622, 2193, 44, 0, 1, 0, 251, 34442, 362997, 101644, 265, 0, 1, 0, 923, 756002, 62924817, 166336604, 6840085, 1854, 0, 1, 0, 3431, 17150366, 11729719509, 305225265804, 136221590695, 630985830, 14833, 0
Offset: 0

Views

Author

Alois P. Heinz, Aug 24 2024

Keywords

Examples

			A(2,2) = 5: 1212, 1221, 2112, 2121, 2211.
A(2,3) = 19: 112122, 112212, 112221, 121122, 121212, 121221, 122112, 122121, 122211, 211122, 211212, 211221, 212112, 212121, 212211, 221112, 221121, 221211, 222111.
A(3,2) = 74: 121323, 121332, 122313, 122331, 123123, 123132, 123213, 123231, 123312, 123321, 131223, 131232, 131322, 132123, 132132, 132312, 132321, 133122, 133212, 133221, 211323, 211332, 212313, 212331, 213123, 213132, 213213, 213231, 213312, 213321, 221313, 221331, 223113, 223131, 223311, 231123, 231132, 231213, 231231, 231312, 231321, 232113, 232131, 232311, 233112, 233121, 233211, 311223, 311232, 311322, 312123, 312132, 312312, 312321, 313122, 313212, 313221, 321123, 321132, 321213, 321231, 321312, 321321, 322113, 322131, 322311, 323112, 323121, 323211, 331122, 331212, 331221, 332112, 332121.
A(4,1) = 9: 2143, 2341, 2413, 3142, 3412, 3421, 4123, 4312, 4321.
Square array A(n,k) begins:
  1,  1,      1,         1,            1,               1, ...
  0,  0,      0,         0,            0,               0, ...
  0,  1,      5,        19,           69,             251, ...
  0,  2,     74,      1622,        34442,          756002, ...
  0,  9,   2193,    362997,     62924817,     11729719509, ...
  0, 44, 101644, 166336604, 305225265804, 623302086965044, ...
		

Crossrefs

Columns k=0-2 give: A000007, A000166, A374980.
Rows n=0-2 give: A000012, A000004, A030662.
Main diagonal gives A375693.

Programs

  • Maple
    A:= (n, k)-> add((-1)^(n-j)*binomial(n, j)*(k*j)!/k!^j, j=0..n):
    seq(seq(A(n, d-n), n=0..d), d=0..10);

Formula

A(n,k) = Sum_{j=0..n} (-1)^(n-j)*binomial(n,j)*(k*j)!/k!^j.

A249619 Triangle T(m,n) = number of permutations of a multiset with m elements and signature corresponding to n-th integer partition (A194602).

Original entry on oeis.org

1, 1, 2, 1, 6, 3, 1, 24, 12, 4, 6, 1, 120, 60, 20, 30, 5, 10, 1, 720, 360, 120, 180, 30, 60, 6, 90, 15, 20, 1, 5040, 2520, 840, 1260, 210, 420, 42, 630, 105, 140, 7, 210, 21, 35, 1, 40320, 20160, 6720, 10080, 1680, 3360, 336, 5040, 840, 1120, 56
Offset: 0

Views

Author

Tilman Piesk, Nov 04 2014

Keywords

Comments

This triangle shows the same numbers in each row as A036038 and A078760 (the multinomial coefficients), but in this arrangement the multisets in column n correspond to the n-th integer partition in the infinite order defined by A194602.
Row lengths: A000041 (partition numbers), Row sums: A005651
Columns: 0: A000142 (factorials), 1: A001710, 2: A001715, 3: A133799, 4: A001720, 6: A001725, 10: A001730, 14: A049388
Last in row: end-2: A037955 after 1 term mismatch, end-1: A001405, end: A000012
The rightmost columns form the triangle A173333:
n 0 1 2 4 6 10 14 21 (A000041(1,2,3...)-1)
m
1 1
2 2 1
3 6 3 1
4 24 12 4 1
5 120 60 20 5 1
6 720 360 120 30 6 1
7 5040 2520 840 210 42 7 1
8 40320 20160 6720 1680 336 56 8 1
A249620 shows the number of partitions of the same multisets. A187783 shows the number of permutations of special multisets.

Examples

			Triangle begins:
  n     0    1    2    3   4   5  6   7   8   9 10
m
0       1
1       1
2       2    1
3       6    3    1
4      24   12    4    6   1
5     120   60   20   30   5  10  1
6     720  360  120  180  30  60  6  90  15  20  1
		

Crossrefs

A198801 Number of closed paths of length 19n whose steps are 19th roots of unity.

Original entry on oeis.org

1, 121645100408832000, 997586474354936812896742294502400000000, 66507379539349211518364492838558005847493108039680000000000000, 11256716378122801825351385824819232115042452248916289339300576523719750000000000000000
Offset: 0

Views

Author

Simon Plouffe, Oct 30 2011

Keywords

Comments

Equivalently, the number of paths of length 19n in Z^19 from {0}^19 to {n}^19. - Andrew Howroyd, Nov 01 2018

Crossrefs

Row n=19 of A187783, column k=19 of A089759.

Programs

Formula

a(n) = (19*n)!/(n!)^19. - Andrew Howroyd, Nov 01 2018

Extensions

Sequence redefined and a(2)-a(4) from Andrew Howroyd, Nov 01 2018
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