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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A293109 Number T(n,k) of multisets of nonempty words with a total of n letters over k-ary alphabet containing the k-th letter such that within each prefix of a word every letter of the alphabet is at least as frequent as the subsequent alphabet letter; triangle T(n,k), n>=0, 0<=k<=n, read by rows.

Original entry on oeis.org

1, 0, 1, 0, 2, 1, 0, 3, 3, 1, 0, 5, 10, 4, 1, 0, 7, 24, 17, 5, 1, 0, 11, 62, 58, 26, 6, 1, 0, 15, 140, 193, 107, 37, 7, 1, 0, 22, 329, 603, 439, 178, 50, 8, 1, 0, 30, 725, 1852, 1663, 852, 275, 65, 9, 1, 0, 42, 1631, 5539, 6283, 3767, 1500, 402, 82, 10, 1
Offset: 0

Views

Author

Alois P. Heinz, Sep 30 2017

Keywords

Examples

			Triangle T(n,k) begins:
  1;
  0,  1;
  0,  2,   1;
  0,  3,   3,   1;
  0,  5,  10,   4,   1;
  0,  7,  24,  17,   5,   1;
  0, 11,  62,  58,  26,   6,  1;
  0, 15, 140, 193, 107,  37,  7, 1;
  0, 22, 329, 603, 439, 178, 50, 8, 1;
		

Crossrefs

Columns k=0-10 give: A000007, A000041 (for n>0), A293797, A293798, A293799, A293800, A293801, A293802, A293803, A293804, A293805.
Row sums give A293110.
T(2n,n) gives A293111.

Programs

  • Maple
    h:= l-> (n-> add(i, i=l)!/mul(mul(1+l[i]-j+add(`if`(l[k]
        n, 0, g(n-i, i, [l[], i])))))
        end:
    A:= proc(n, k) option remember; `if`(n=0, 1, add(add(g(d, k, [])
          *d, d=numtheory[divisors](j))*A(n-j, k), j=1..n)/n)
        end:
    T:= (n, k)-> A(n, k) -`if`(k=0, 0, A(n, k-1)):
    seq(seq(T(n, k), k=0..n), n=0..12);
  • Mathematica
    h[l_] := Function[n, Total[l]!/Product[Product[1 + l[[i]] - j + Sum[If[l[[k]] < j, 0, 1], {k, i + 1, n}], {j, 1, l[[i]]}], {i, n}]][Length[l]];
    g[n_, i_, l_] := g[n, i, l] = If[n == 0, h[l], If[i < 1, 0, If[i == 1, h[Join[l, Table[1, n]]], g[n, i - 1, l] + If[i > n, 0, g[n - i, i, Append[l, i]]]]]];
    A[n_, k_] := A[n, k] = If[n == 0, 1, Sum[Sum[g[d, k, {}]*d, {d, Divisors[j]}]*A[n - j, k], {j, 1, n}]/n];
    T[n_, 0] := A[n, 0]; T[n_, k_] := A[n, k] - A[n, k - 1];
    Table[T[n, k], {n, 0, 12}, {k, 0, n}] // Flatten (* Jean-François Alcover, Jul 09 2018, after Alois P. Heinz *)

Formula

T(n,k) = A293108(n,k) - A293108(n,k-1) for k>0, T(n,0) = A293108(n,0).

A293113 Number T(n,k) of sets of nonempty words with a total of n letters over k-ary alphabet containing the k-th letter such that within each prefix of a word every letter of the alphabet is at least as frequent as the subsequent alphabet letter; triangle T(n,k), n>=0, 0<=k<=n, read by rows.

Original entry on oeis.org

1, 0, 1, 0, 1, 1, 0, 2, 3, 1, 0, 2, 8, 4, 1, 0, 3, 20, 16, 5, 1, 0, 4, 47, 53, 25, 6, 1, 0, 5, 106, 173, 102, 36, 7, 1, 0, 6, 237, 532, 410, 172, 49, 8, 1, 0, 8, 522, 1615, 1545, 813, 268, 64, 9, 1, 0, 10, 1146, 4785, 5784, 3576, 1448, 394, 81, 10, 1
Offset: 0

Views

Author

Alois P. Heinz, Sep 30 2017

Keywords

Examples

			Triangle T(n,k) begins:
  1;
  0, 1;
  0, 1,   1;
  0, 2,   3,   1;
  0, 2,   8,   4,   1;
  0, 3,  20,  16,   5,   1;
  0, 4,  47,  53,  25,   6,  1;
  0, 5, 106, 173, 102,  36,  7, 1;
  0, 6, 237, 532, 410, 172, 49, 8, 1;
  ...
		

Crossrefs

Columns k=0-10 give: A000007, A000009 (for n>0), A293883, A293884, A293885, A293886, A293887, A293888, A293889, A293890, A293891.
Row sums give A293114.
T(2n,n) gives A293115.

Programs

  • Maple
    h:= l-> (n-> add(i, i=l)!/mul(mul(1+l[i]-j+add(`if`(l[k]
        n, 0, g(n-i, i, [l[], i])))))
        end:
    b:= proc(n, i, k) option remember; `if`(n=0, 1, `if`(i<1, 0,
          add(b(n-i*j, i-1, k)*binomial(g(i, k, []), j), j=0..n/i)))
        end:
    T:= (n, k)-> b(n$2, k)-`if`(k=0, 0, b(n$2, k-1)):
    seq(seq(T(n, k), k=0..n), n=0..14);
  • Mathematica
    h[l_] := Function[n, Total[l]!/Product[Product[1 + l[[i]] - j + Sum[If[ l[[k]] n, 0, g[n - i, i, Append[l, i]]]]]];
    b[n_, i_, k_] := b[n, i, k] = If[n == 0, 1, If[i<1, 0, Sum[b[n - i*j, i-1, k]*Binomial[g[i, k, {}], j], {j, 0, n/i}]]];
    T[n_, k_] := b[n, n, k] - If[k == 0, 0, b[n, n, k - 1]];
    Table[T[n, k], {n, 0, 14}, {k, 0, n}] // Flatten (* Jean-François Alcover, Jun 04 2018, after Alois P. Heinz *)

Formula

T(n,k) = A293112(n,k) - A293112(n,k-1) for k>0, T(n,0) = A293112(n,0).

A293108 Number A(n,k) of multisets of nonempty words with a total of n letters over k-ary alphabet such that within each prefix of a word every letter of the alphabet is at least as frequent as the subsequent alphabet letter; square array A(n,k), n>=0, k>=0, read by antidiagonals.

Original entry on oeis.org

1, 1, 0, 1, 1, 0, 1, 1, 2, 0, 1, 1, 3, 3, 0, 1, 1, 3, 6, 5, 0, 1, 1, 3, 7, 15, 7, 0, 1, 1, 3, 7, 19, 31, 11, 0, 1, 1, 3, 7, 20, 48, 73, 15, 0, 1, 1, 3, 7, 20, 53, 131, 155, 22, 0, 1, 1, 3, 7, 20, 54, 157, 348, 351, 30, 0, 1, 1, 3, 7, 20, 54, 163, 455, 954, 755, 42, 0
Offset: 0

Views

Author

Alois P. Heinz, Sep 30 2017

Keywords

Examples

			Square array A(n,k) begins:
  1,  1,   1,   1,   1,   1,   1,   1, ...
  0,  1,   1,   1,   1,   1,   1,   1, ...
  0,  2,   3,   3,   3,   3,   3,   3, ...
  0,  3,   6,   7,   7,   7,   7,   7, ...
  0,  5,  15,  19,  20,  20,  20,  20, ...
  0,  7,  31,  48,  53,  54,  54,  54, ...
  0, 11,  73, 131, 157, 163, 164, 164, ...
  0, 15, 155, 348, 455, 492, 499, 500, ...
		

Crossrefs

Main diagonal gives A293110.

Programs

  • Maple
    h:= l-> (n-> add(i, i=l)!/mul(mul(1+l[i]-j+add(`if`(l[k]
        n, 0, g(n-i, i, [l[], i])))))
        end:
    A:= proc(n, k) option remember; `if`(n=0, 1, add(add(g(d, k, [])
          *d, d=numtheory[divisors](j))*A(n-j, k), j=1..n)/n)
        end:
    seq(seq(A(n, d-n), n=0..d), d=0..14);
  • Mathematica
    h[l_] := Function [n, Total[l]!/Product[Product[1 + l[[i]] - j + Sum[If[ l[[k]] < j, 0, 1], {k, i+1, n}], {j, 1, l[[i]]}], {i, n}]][Length[l]];
    g[n_, i_, l_] := g[n, i, l] = If[n == 0, h[l], If[i < 1, 0, If[i == 1, h[Join[l, Table[1, n]]], g[n, i - 1, l] + If[i > n, 0, g[n - i, i, Append[l, i]]]]]];
    A[n_, k_] := A[n, k] = If[n == 0, 1, Sum[Sum[g[d, k, {}]*d, {d, Divisors[j] }]*A[n - j, k], {j, 1, n}]/n];
    Table[A[n, d-n], {d, 0, 14}, {n, 0, d}] // Flatten (* Jean-François Alcover, Jun 03 2018, from Maple *)

Formula

G.f. of column k: Product_{j>=1} 1/(1-x^j)^A182172(j,k).
A(n,k) = Sum_{j=0..k} A293109(n,j).
A(n,n) = A(n,k) for all k >= n.

A293112 Number A(n,k) of sets of nonempty words with a total of n letters over k-ary alphabet such that within each prefix of a word every letter of the alphabet is at least as frequent as the subsequent alphabet letter; square array A(n,k), n>=0, k>=0, read by antidiagonals.

Original entry on oeis.org

1, 1, 0, 1, 1, 0, 1, 1, 1, 0, 1, 1, 2, 2, 0, 1, 1, 2, 5, 2, 0, 1, 1, 2, 6, 10, 3, 0, 1, 1, 2, 6, 14, 23, 4, 0, 1, 1, 2, 6, 15, 39, 51, 5, 0, 1, 1, 2, 6, 15, 44, 104, 111, 6, 0, 1, 1, 2, 6, 15, 45, 129, 284, 243, 8, 0, 1, 1, 2, 6, 15, 45, 135, 386, 775, 530, 10, 0
Offset: 0

Views

Author

Alois P. Heinz, Sep 30 2017

Keywords

Examples

			Square array A(n,k) begins:
  1, 1,   1,   1,   1,   1,   1,   1, ...
  0, 1,   1,   1,   1,   1,   1,   1, ...
  0, 1,   2,   2,   2,   2,   2,   2, ...
  0, 2,   5,   6,   6,   6,   6,   6, ...
  0, 2,  10,  14,  15,  15,  15,  15, ...
  0, 3,  23,  39,  44,  45,  45,  45, ...
  0, 4,  51, 104, 129, 135, 136, 136, ...
  0, 5, 111, 284, 386, 422, 429, 430, ...
		

Crossrefs

Main diagonal gives A293114.

Programs

  • Maple
    h:= l-> (n-> add(i, i=l)!/mul(mul(1+l[i]-j+add(`if`(l[k]
        n, 0, g(n-i, i, [l[], i])))))
        end:
    b:= proc(n, i, k) option remember; `if`(n=0, 1, `if`(i<1, 0,
          add(b(n-i*j, i-1, k)*binomial(g(i, k, []), j), j=0..n/i)))
        end:
    A:= (n, k)-> b(n$2, k):
    seq(seq(A(n, d-n), n=0..d), d=0..14);
  • Mathematica
    h[l_] := Function[n, Total[l]!/Product[Product[1 + l[[i]] - j + Sum[If[ l[[k]] n, 0, g[n - i, i, Append[l, i]]]]]];
    b[n_, i_, k_] := b[n, i, k] = If[n == 0, 1, If[i < 1, 0, Sum[b[n - i*j, i - 1, k]*Binomial[g[i, k, {}], j], {j, 0, n/i}]]];
    A[n_, k_] := b[n, n, k];
    Table[A[n, d-n], {d, 0, 14}, {n, 0, d}] // Flatten (* Jean-François Alcover, Jun 03 2018, from Maple *)

Formula

G.f. of column k: Product_{j>=1} (1+x^j)^A182172(j,k).
A(n,k) = Sum_{j=0..k} A293113(n,j).

A182222 Number T(n,k) of standard Young tableaux of n cells and height >= k; triangle T(n,k), n>=0, 0<=k<=n, read by rows.

Original entry on oeis.org

1, 1, 1, 2, 2, 1, 4, 4, 3, 1, 10, 10, 9, 4, 1, 26, 26, 25, 16, 5, 1, 76, 76, 75, 56, 25, 6, 1, 232, 232, 231, 197, 105, 36, 7, 1, 764, 764, 763, 694, 441, 176, 49, 8, 1, 2620, 2620, 2619, 2494, 1785, 856, 273, 64, 9, 1, 9496, 9496, 9495, 9244, 7308, 3952, 1506, 400, 81, 10, 1
Offset: 0

Views

Author

Alois P. Heinz, Apr 19 2012

Keywords

Comments

Also number of self-inverse permutations in S_n with longest increasing subsequence of length >= k. T(4,3) = 4: 1234, 1243, 1324, 2134; T(3,0) = T(3,1) = 4: 123, 132, 213, 321; T(5,3) = 16: 12345, 12354, 12435, 12543, 13245, 13254, 14325, 14523, 15342, 21345, 21354, 21435, 32145, 34125, 42315, 52341.

Examples

			T(4,3) = 4, there are 4 standard Young tableaux of 4 cells and height >= 3:
  +---+   +------+   +------+   +------+
  | 1 |   | 1  2 |   | 1  3 |   | 1  4 |
  | 2 |   | 3 .--+   | 2 .--+   | 2 .--+
  | 3 |   | 4 |      | 4 |      | 3 |
  | 4 |   +---+      +---+      +---+
  +---+
Triangle T(n,k) begins:
    1;
    1,   1;
    2,   2,   1;
    4,   4,   3,   1;
   10,  10,   9,   4,   1;
   26,  26,  25,  16,   5,   1;
   76,  76,  75,  56,  25,   6,  1;
  232, 232, 231, 197, 105,  36,  7,  1;
  764, 764, 763, 694, 441, 176, 49,  8,  1;
  ...
		

Crossrefs

Diagonal and lower diagonals give: A000012, A000027(n+1), A000290(n+1) for n>0, A131423(n+1) for n>1.
T(2n,n) gives A318289.

Programs

  • Maple
    h:= proc(l) local n; n:=nops(l); add(i, i=l)! /mul(mul(1+l[i]-j+
           add(`if`(l[k]>=j, 1, 0), k=i+1..n), j=1..l[i]), i=1..n)
        end:
    g:= proc(n, i, l) option remember;
          `if`(n=0, h(l), `if`(i<1, 0, `if`(i=1, h([l[], 1$n]),
            g(n, i-1, l) +`if`(i>n, 0, g(n-i, i, [l[], i])))))
        end:
    T:= (n, k)-> g(n, n, []) -`if`(k=0, 0, g(n, k-1, [])):
    seq(seq(T(n, k), k=0..n), n=0..12);
  • Mathematica
    h[l_] := Module[{n = Length[l]}, Sum[i, {i, l}]! / Product[ Product[1 + l[[i]] - j + Sum [If[l[[k]] >= j, 1, 0], {k, i+1, n}], {j, 1, l[[i]]}], {i, 1, n}]];
    g[n_, i_, l_] := g[n, i, l] = If[n == 0, h[l], If[i < 1, 0, If[i == 1, h[Join[l, Array[1&, n]]], g [n, i-1, l] + If[i > n, 0, g[n-i, i, Append[l, i]]]]]];
    t[n_, k_] := g[n, n, {}] - If[k == 0, 0, g[n, k-1, {}]];
    Table[Table[t[n, k], {k, 0, n}], {n, 0, 12}] // Flatten (* Jean-François Alcover, Dec 12 2013, translated from Maple *)

Formula

T(n,k) = A182172(n,n) - A182172(n,k-1) for k>0, T(n,0) = A182172(n,n).

A240608 Number A(n,k) of n-length words w over a k-ary alphabet such that w is empty or a prefix z concatenated with letter a_i and i=1 or 0 < #(z,a_{i-1}) >= #(z,a_i), where #(z,a_i) counts the occurrences of the i-th letter in z; square array A(n,k), n>=0, k>=0, read by antidiagonals.

Original entry on oeis.org

1, 1, 0, 1, 1, 0, 1, 1, 1, 0, 1, 1, 2, 1, 0, 1, 1, 2, 4, 1, 0, 1, 1, 2, 5, 7, 1, 0, 1, 1, 2, 5, 13, 14, 1, 0, 1, 1, 2, 5, 14, 35, 25, 1, 0, 1, 1, 2, 5, 14, 45, 94, 50, 1, 0, 1, 1, 2, 5, 14, 46, 149, 254, 91, 1, 0, 1, 1, 2, 5, 14, 46, 164, 509, 688, 182, 1, 0, 1, 1, 2, 5, 14, 46, 165, 629, 1756, 1872, 336, 1, 0
Offset: 0

Views

Author

Alois P. Heinz, Apr 09 2014

Keywords

Examples

			Square array A(n,k) begins:
  1, 1,  1,   1,    1,    1,    1,    1,    1, ...
  0, 1,  1,   1,    1,    1,    1,    1,    1, ...
  0, 1,  2,   2,    2,    2,    2,    2,    2, ...
  0, 1,  4,   5,    5,    5,    5,    5,    5, ...
  0, 1,  7,  13,   14,   14,   14,   14,   14, ...
  0, 1, 14,  35,   45,   46,   46,   46,   46, ...
  0, 1, 25,  94,  149,  164,  165,  165,  165, ...
  0, 1, 50, 254,  509,  629,  650,  651,  651, ...
  0, 1, 91, 688, 1756, 2511, 2742, 2770, 2771, ...
		

Crossrefs

Columns k=0-10 give: A000007, A000012, A026010(n-1) for n>0, A240609, A240610, A240611, A240612, A240613, A240614, A240615, A240616.
Main diagonal gives A240617.
Cf. A182172.

Programs

  • Maple
    b:= proc(n, k, l) option remember; `if`(n=0, 1, `if`(nops(l) b(n, min(k, n), []):
    seq(seq(A(n, d-n), n=0..d), d=0..14);
  • Mathematica
    b[n_, k_, l_List] := b[n, k, l] = If[n == 0, 1, If[Length[l] l[[i]]+1]], 0], {i, 1, Length[l]}]]; A[n_, k_] := b[n, Min[k, n], {}]; Table[ Table[A[n, d-n], {n, 0, d}], {d, 0, 14}] // Flatten (* Jean-François Alcover, Jan 19 2015, after Alois P. Heinz *)

A293110 Number of multisets of nonempty words with a total of n letters over n-ary alphabet such that within each prefix of a word every letter of the alphabet is at least as frequent as the subsequent alphabet letter.

Original entry on oeis.org

1, 1, 3, 7, 20, 54, 164, 500, 1630, 5472, 19257, 70133, 265858, 1042346, 4235031, 17760943, 76913277, 342919431, 1573637985, 7415371293, 35860511131, 177641956111, 900782461170, 4668600610346, 24714284921937, 133467868645017, 734844788634269, 4120752558254581
Offset: 0

Views

Author

Alois P. Heinz, Sep 30 2017

Keywords

Examples

			a(0) = 1: {}.
a(1) = 1: {a}
a(2) = 3: {a,a}, {aa}, {ab}.
a(3) = 7: {a,a,a}, {a,aa}, {a,ab}, {aaa}, {aab}, {aba}, {abc}.
		

Crossrefs

Main diagonal of A293108.
Row sums of A293109 and of A293808.

Programs

  • Maple
    g:= proc(n) option remember;
          `if`(n<2, 1, g(n-1)+(n-1)*g(n-2))
        end:
    a:= proc(n) option remember; `if`(n=0, 1, add(add(g(d)
          *d, d=numtheory[divisors](j))*a(n-j), j=1..n)/n)
        end:
    seq(a(n), n=0..40);
  • Mathematica
    g[n_] := g[n] = If[n < 2, 1, g[n - 1] + (n - 1)*g[n - 2]];
    a[n_] := a[n] = If[n == 0, 1, Sum[Sum[g[d]*d, {d, Divisors[j]}]*a[n - j], {j, 1, n}]/n];
    Table[a[n], {n, 0, 40}] (* Jean-François Alcover, Jun 07 2018, from Maple *)

Formula

G.f.: Product_{j>=1} 1/(1-x^j)^A000085(j).

A007580 Number of Young tableaux of height <= 8.

Original entry on oeis.org

1, 1, 2, 4, 10, 26, 76, 232, 764, 2619, 9486, 35596, 139392, 562848, 2352064, 10092160, 44546320, 201158620, 930213752, 4387327088, 21115314916, 103386386516, 515097746072, 2605341147472, 13378787264584, 69622529312665, 367161088308490, 1959294979429380
Offset: 0

Views

Author

Keywords

Comments

Also the number of n-length words w over 8-ary alphabet {a1,a2,...,a8} such that for every prefix z of w we have #(z,a1) >= #(z,a2) >= ... >= #(z,a8), where #(z,x) counts the letters x in word z. - Alois P. Heinz, May 30 2012

References

  • N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

Crossrefs

Column k=8 of A182172. - Alois P. Heinz, May 30 2012

Programs

  • Maple
    h:= proc(l) local n; n:=nops(l); add(i, i=l)! /mul(mul(1+l[i]-j+
          add(`if`(l[k]>=j, 1, 0), k=i+1..n), j=1..l[i]), i=1..n)
        end:
    g:= proc(n, i, l) option remember;
          `if`(n=0, h(l), `if`(i=1, h([l[], 1$n]), `if`(i<1, 0,
            g(n, i-1, l) +`if`(i>n, 0, g(n-i, i, [l[], i])))))
        end:
    a:= n-> g(n, 8, []):
    seq(a(n), n=0..30); # Alois P. Heinz, Apr 10 2012
    # second Maple program:
    a:= proc(n) option remember;
          `if`(n<4, [1, 1, 2, 4][n+1],
           ((40*n^3+1084*n^2+8684*n+18480)*a(n-1)
           +16*(n-1)*(5*n^3+107*n^2+610*n+600)*a(n-2)
           -1024*(n-1)*(n-2)*(n+6)*a(n-3)
           -1024*(n-1)*(n-2)*(n-3)*(n+4)*a(n-4)) /
           ((n+7)*(n+12)*(n+15)*(n+16)))
        end:
    seq(a(n), n=0..30);  # Alois P. Heinz, Oct 12 2012
  • Mathematica
    RecurrenceTable[{1024 (-3+n) (-2+n) (-1+n) (4+n) a[-4+n]+1024 (-2+n) (-1+n) (6+n) a[-3+n]-16 (-1+n) (600+610 n+107 n^2+5 n^3) a[-2+n]-4 (4620+2171 n+271 n^2+10 n^3) a[-1+n]+(7+n) (12+n) (15+n) (16+n) a[n]==0,a[1]==1,a[2]==2,a[3]==4,a[4]==10}, a, {n, 20}] (* Vaclav Kotesovec, Sep 11 2013 *)

Formula

a(n) ~ 135/16 * 8^(n+14)/(Pi^2*n^14). - Vaclav Kotesovec, Sep 11 2013

Extensions

More terms from Alois P. Heinz, Apr 10 2012

A212915 Number of standard Young tableaux of n cells and height <= 9.

Original entry on oeis.org

1, 1, 2, 4, 10, 26, 76, 232, 764, 2620, 9495, 35685, 140031, 567503, 2382394, 10290308, 45780063, 208852719, 977152266, 4674398032, 22854255698, 113957313538, 579157509082, 2995214721530, 15752586526189, 84145056172981, 456221504976506, 2508227921637772
Offset: 0

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Author

Alois P. Heinz, May 30 2012

Keywords

Comments

Number of standard Young tableaux of n cells and <= 9 columns.
Also the number of n-length words w over 9-ary alphabet {a1,a2,...,a9} such that for every prefix z of w we have #(z,a1) >= #(z,a2) >= ... >= #(z,a9), where #(z,x) counts the letters x in word z.

Crossrefs

Column k=9 of A182172.

Programs

  • Maple
    h:= proc(l) local n; n:=nops(l); add(i, i=l)! /mul(mul(1+l[i]-j+
          add(`if`(l[k]>=j, 1, 0), k=i+1..n), j=1..l[i]), i=1..n)
        end:
    g:= proc(n, i, l) option remember;
          `if`(n=0, h(l), `if`(i=1, h([l[], 1$n]), `if`(i<1, 0,
            g(n, i-1, l) +`if`(i>n, 0, g(n-i, i, [l[], i])))))
        end:
    a:= n-> g(n, 9, []):
    seq(a(n), n=0..30);
    # second Maple program:
    a:= proc(n) option remember;
          `if`(n<5, [1, 1, 2, 4, 10][n+1],
          ((5*n^4+230*n^3+3574*n^2+20663*n+29393)*a(n-1)
           +7*(n-1)*(10*n^3+266*n^2+1919*n+2713)*a(n-2)
           -(n-1)*(n-2)*(230*n^2+3934*n+13587)*a(n-3)
           -3*(n-1)*(n-2)*(n-3)*(263*n+1414)*a(n-4)
           +945*(n-1)*(n-2)*(n-3)*(n-4)*a(n-5)) /
           ((n+20)*(n+8)*(n+18)*(n+14)))
        end:
    seq(a(n), n=0..30);  # Alois P. Heinz, Oct 12 2012
  • Mathematica
    Flatten[{1,RecurrenceTable[{-945 (-4+n) (-3+n) (-2+n) (-1+n) a[-5+n]+3 (-3+n) (-2+n) (-1+n) (1414+263 n) a[-4+n]+(-2+n) (-1+n) (13587+3934 n+230 n^2) a[-3+n]-7 (-1+n) (2713+1919 n+266 n^2+10 n^3) a[-2+n]+(-29393-20663 n-3574 n^2-230 n^3-5 n^4) a[-1+n]+(8+n) (14+n) (18+n) (20+n) a[n]==0,a[1]==1,a[2]==2,a[3]==4,a[4]==10,a[5]==26}, a, {n, 20}]}] (* Vaclav Kotesovec, Sep 11 2013 *)

Formula

a(n) ~ 14175/256 * 9^(n+18)/(Pi^2*n^18). - Vaclav Kotesovec, Sep 11 2013

A212916 Number of standard Young tableaux of n cells and height <= 10.

Original entry on oeis.org

1, 1, 2, 4, 10, 26, 76, 232, 764, 2620, 9496, 35695, 140140, 568360, 2389192, 10338315, 46118592, 211120144, 992316928, 4773362476, 23500234512, 118125854560, 606106812640, 3168660576795, 16872323635132, 91369920670420, 503022250919640, 2811920834508705
Offset: 0

Views

Author

Alois P. Heinz, May 30 2012

Keywords

Comments

Number of standard Young tableaux of n cells and <= 10 columns.
Also the number of n-length words w over 10-ary alphabet {a1,a2,...,a10} such that for every prefix z of w we have #(z,a1) >= #(z,a2) >= ... >= #(z,a10), where #(z,x) counts the letters x in word z.
Conjecture: generally (for tableaux with height <= k), a(n) ~ k^n/Pi^(k/2) * (k/n)^(k*(k-1)/4) * prod(j=1..k,Gamma(j/2)); set k=10 for this sequence. - Vaclav Kotesovec, Sep 12 2013

Crossrefs

Column k=10 of A182172.

Programs

  • Maple
    h:= proc(l) local n; n:=nops(l); add(i, i=l)! /mul(mul(1+l[i]-j+
          add(`if`(l[k]>=j, 1, 0), k=i+1..n), j=1..l[i]), i=1..n)
        end:
    g:= proc(n, i, l) option remember;
          `if`(n=0, h(l), `if`(i=1, h([l[], 1$n]), `if`(i<1, 0,
            g(n, i-1, l) +`if`(i>n, 0, g(n-i, i, [l[], i])))))
        end:
    a:= n-> g(n, 10, []):
    seq(a(n), n=0..30);
    # second Maple program:
    a:= proc(n) option remember;
          `if`(n<6, [1, 1, 2, 4, 10, 26][n+1],
          ((70*n^4+4144*n^3+84986*n^2+685800*n+1656000)*a(n-1)
           +4*(n-1)*(35*n^4+1778*n^3+30106*n^2+184221*n+244350)*a(n-2)
           -8*(n-1)*(n-2)*(518*n^2+11916*n+59265)*a(n-3)
           -16*(n-1)*(n-2)*(n-3)*(259*n^2+4819*n+17355)*a(n-4)
           +21600*(n-1)*(n-2)*(n-3)*(n-4)*a(n-5)
           +14400*(n-5)*(n-1)*(n-2)*(n-3)*(n-4)*a(n-6)) /
           ((n+21)*(n+9)*(n+16)*(n+25)*(n+24)))
        end:
    seq(a(n), n=0..30);  # Alois P. Heinz, Oct 12 2012
  • Mathematica
    Flatten[{1,RecurrenceTable[{-14400 (-5+n) (-4+n) (-3+n) (-2+n) (-1+n) a[-6+n]-21600 (-4+n) (-3+n) (-2+n) (-1+n) a[-5+n]+16 (-3+n) (-2+n) (-1+n) (17355+4819 n+259 n^2) a[-4+n]+8 (-2+n) (-1+n) (59265+11916 n+518 n^2) a[-3+n]-4 (-1+n) (244350+184221 n+30106 n^2+1778 n^3+35 n^4) a[-2+n]-2 (828000+342900 n+42493 n^2+2072 n^3+35 n^4) a[-1+n]+(9+n) (16+n) (21+n) (24+n) (25+n) a[n]==0, a[1]==1, a[2]==2, a[3]==4, a[4]==10, a[5]==26, a[6]==76}, a, {n, 20}]}] (* Vaclav Kotesovec, Sep 11 2013 *)

Formula

a(n) ~ 42525/32 * 10^(n+45/2)/(Pi^(5/2)*n^(45/2)). - Vaclav Kotesovec, Sep 11 2013
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