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.

Showing 1-6 of 6 results.

A237770 Number of standard Young tableaux with n cells without a succession v, v+1 in a row.

Original entry on oeis.org

1, 1, 1, 2, 4, 9, 22, 59, 170, 516, 1658, 5583, 19683, 72162, 274796, 1082439, 4406706, 18484332, 79818616, 353995743, 1611041726, 7510754022, 35842380314, 174850257639, 871343536591, 4430997592209, 22978251206350, 121410382810005, 653225968918521
Offset: 0

Views

Author

Joerg Arndt and Alois P. Heinz, Feb 13 2014

Keywords

Comments

A standard Young tableau (SYT) without a succession v, v+1 in a row is called a nonconsecutive tableau.
Also the number of ballot sequences without two consecutive elements equal. A ballot sequence B is a string such that, for all prefixes P of B, h(i)>=h(j) for iA000085).
First column (k=0) of A238125.

Examples

			The a(5) = 9 such tableaux of 5 are:
[1]   [2]  [3]   [4]  [5]  [6]  [7]  [8]  [9]
135   13   135   13   13   14   14   15   1
24    24   2     25   2    25   2    2    2
      5    4     4    4    3    3    3    3
                      5         5    4    4
                                          5
The corresponding ballot sequences are:
1:  [ 0 1 0 1 0 ]
2:  [ 0 1 0 1 2 ]
3:  [ 0 1 0 2 0 ]
4:  [ 0 1 0 2 1 ]
5:  [ 0 1 0 2 3 ]
6:  [ 0 1 2 0 1 ]
7:  [ 0 1 2 0 3 ]
8:  [ 0 1 2 3 0 ]
9:  [ 0 1 2 3 4 ]
		

Crossrefs

Cf. A000085 (all Young tableaux), A000957, A001181, A214021, A214087, A214159, A214875.
Cf. A238126 (tableaux with one succession), A238127 (two successions).

Programs

  • Maple
    h:= proc(l, j) option remember; `if`(l=[], 1,
          `if`(l[1]=0, h(subsop(1=[][], l), j-1), add(
          `if`(i<>j and l[i]>0 and (i=1 or l[i]>l[i-1]),
           h(subsop(i=l[i]-1, l), i), 0), i=1..nops(l))))
        end:
    g:= proc(n, i, l) `if`(n=0 or i=1, h([1$n, l[]], 0),
          `if`(i<1, 0, g(n, i-1, l)+
          `if`(i>n, 0, g(n-i, i, [i, l[]]))))
        end:
    a:= n-> g(n, n, []):
    seq(a(n), n=0..30);
    # second Maple program (counting ballot sequences):
    b:= proc(n, v, l) option remember;
          `if`(n<1, 1, add(`if`(i<>v and (i=1 or l[i-1]>l[i]),
           b(n-1, i, subsop(i=l[i]+1, l)), 0), i=1..nops(l))+
           b(n-1, nops(l)+1, [l[], 1]))
        end:
    a:= proc(n) option remember; forget(b); b(n-1, 1, [1]) end:
    seq(a(n), n=0..30);
  • Mathematica
    b[n_, v_, l_List] := b[n, v, l] = If[n<1, 1, Sum[If[i != v && (i == 1 || l[[i-1]] > l[[i]]), b[n-1, i, ReplacePart[l, i -> l[[i]]+1]], 0], {i, 1, Length[l]}] + b[n-1, Length[l]+1, Append[l, 1]]]; a[n_] := a[n] = b[n-1, 1, {1}]; Table[a[n], {n, 0, 30}] (* Jean-François Alcover, Feb 06 2015, translated from 2nd Maple program *)

Formula

a(n) = Sum_{k=1..A264078(n)} k * A264051(n,k). - Alois P. Heinz, Nov 02 2015

A214088 Number A(n,k) of n X k nonconsecutive chess tableaux; square array A(n,k), n>=0, k>=0, read by antidiagonals.

Original entry on oeis.org

1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 0, 0, 1, 1, 1, 0, 0, 1, 1, 1, 1, 0, 0, 1, 0, 1, 1, 1, 0, 0, 1, 1, 2, 1, 1, 1, 0, 0, 1, 0, 7, 0, 1, 1, 1, 0, 0, 1, 1, 35, 27, 5, 1, 1, 1, 0, 0, 1, 0, 212, 0, 128, 0, 1, 1, 1, 0, 0, 1, 1, 1421, 5075, 6212, 640, 14, 1, 1, 1, 0, 0, 1, 0, 10128, 0, 430275, 0, 3351, 0, 1, 1
Offset: 0

Views

Author

Alois P. Heinz, Jul 02 2012

Keywords

Comments

A standard Young tableau (SYT) with cell(i,j)+i+j == 1 mod 2 for all cells where entries m and m+1 never appear in the same row is called a nonconsecutive chess tableau.

Examples

			A(3,5) = 1:
  [1 4 7 10 13]
  [2 5 8 11 14]
  [3 6 9 12 15].
A(7,2) = 5:
  [1  8]   [1  6]   [1  4]   [1   6]   [1   4]
  [2  9]   [2  7]   [2  5]   [2   7]   [2   5]
  [3 10]   [3 10]   [3 10]   [3   8]   [3   8]
  [4 11]   [4 11]   [6 11]   [4   9]   [6   9]
  [5 12]   [5 12]   [7 12]   [5  12]   [7  12]
  [6 13]   [8 13]   [8 13]   [10 13]   [10 13]
  [7 14]   [9 14]   [9 14]   [11 14]   [11 14].
Square array A(n,k) begins:
  1,  1,  1,   1,    1,      1,        1,          1, ...
  1,  1,  0,   0,    0,      0,        0,          0, ...
  1,  1,  0,   0,    0,      0,        0,          0, ...
  1,  1,  1,   1,    1,      1,        1,          1, ...
  1,  1,  0,   1,    0,      1,        0,          1, ...
  1,  1,  2,   7,   35,    212,     1421,      10128, ...
  1,  1,  0,  27,    0,   5075,        0,    2402696, ...
  1,  1,  5, 128, 6212, 430275, 42563460, 5601745187, ...
		

Crossrefs

Cf. A000108 (bisection of column k=2 for n>0), A214459 (column k=3), A214460 (bisection of row n=4), A214461 (row n=5), A214020, A214021.

Programs

  • Maple
    b:= proc(l, t) option remember; local n, s;
           n, s:= nops(l), add(i, i=l);
          `if`(s=0, 1, add(`if`(t<>i and irem(s+i-l[i], 2)=1 and l[i]>
          `if`(i=n, 0, l[i+1]), b(subsop(i=l[i]-1, l), i), 0), i=1..n))
        end:
    A:= (n, k)-> `if`(n<1 or k<1, 1, b([k$n], 0)):
    seq(seq(A(n, d-n), n=0..d), d=0..14);
  • Mathematica
    b[l_, t_] := b[l, t] = Module[{n, s}, {n, s} = {Length[l], Sum[i, {i, l}]};
    If[s == 0, 1, Sum[If[t != i && Mod[s + i - l[[i]], 2] == 1 && l[[i]] > If[i == n, 0, l[[i+1]]], b[ReplacePart[l, {i -> l[[i]]-1}], i], 0], {i, 1, n}]] ]; a [n_, k_] := If[n < 1 || k < 1, 1, b[Array[k&, n], 0]]; Table[Table[a[n, d-n], {n, 0, d}], {d, 0, 14}] // Flatten (* Jean-François Alcover, Dec 11 2013, translated from Maple *)

A214020 Number A(n,k) of n X k chess tableaux; square array A(n,k), n>=0, k>=0, read by antidiagonals.

Original entry on oeis.org

1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 2, 0, 1, 1, 1, 1, 2, 6, 6, 2, 1, 1, 1, 1, 0, 22, 0, 22, 0, 1, 1, 1, 1, 5, 92, 324, 324, 92, 5, 1, 1, 1, 1, 0, 422, 0, 8716, 0, 422, 0, 1, 1, 1, 1, 14, 2074, 47570, 343234, 343234, 47570, 2074, 14, 1, 1
Offset: 0

Views

Author

Alois P. Heinz, Jul 01 2012

Keywords

Comments

A standard Young tableau (SYT) with cell(i,j)+i+j == 1 mod 2 for all cells is called a chess tableau. The definition appears first in the article by Jonas Sjöstrand.

Examples

			A(4,3) = A(3,4) = 6:
  [1 4  7]  [1 4  5]  [1 2  3]  [1 4  7]  [ 1  4  7]  [ 1  2  3]
  [2 5 10]  [2 7 10]  [4 7 10]  [2 5 10]  [ 2  5  8]  [ 4  5  6]
  [3 8 11]  [3 8 11]  [5 8 11]  [3 6 11]  [ 3  6  9]  [ 7  8  9]
  [6 9 12]  [6 9 12]  [6 9 12]  [8 9 12]  [10 11 12]  [10 11 12].
Square array A(n,k) begins:
  1,  1,  1,   1,     1,        1,          1,             1, ...
  1,  1,  1,   1,     1,        1,          1,             1, ...
  1,  1,  0,   1,     0,        2,          0,             5, ...
  1,  1,  1,   2,     6,       22,         92,           422, ...
  1,  1,  0,   6,     0,      324,          0,         47570, ...
  1,  1,  2,  22,   324,     8716,     343234,      17423496, ...
  1,  1,  0,  92,     0,   343234,          0,    8364334408, ...
  1,  1,  5, 422, 47570, 17423496, 8364334408, 6873642982160, ...
		

Crossrefs

Cf. A000108 (bisection of row 2), A001181 (row 3), A108774, A214021, A214088.

Programs

  • Maple
    b:= proc() option remember; local s; s:= add(i, i=args); `if`(s=0, 1,
          add(`if`(irem(s+i-args[i], 2)=1 and args[i]>`if`(i=nargs, 0,
          args[i+1]), b(subsop(i=args[i]-1, [args])[]), 0), i=1..nargs))
        end:
    A:= (n, k)-> `if`(n
    				
  • Mathematica
    b[args_List] := b[args] = Module[{s = Total[args], nargs = Length[args]}, If[s == 0, 1, Sum[If[Mod[s + i - args[[i]], 2] == 1 && args[[i]] > If[i == nargs, 0, args[[i + 1]]], b[ReplacePart[args, i -> args[[i]] - 1]], 0], {i, 1, nargs}]]]; A[n_, k_] := If[n < k, A[k, n], If[k < 2, 1, b[Array[n &, k]]]]; Table[Table[A[n, d - n], {n, 0, d}], {d, 0, 12}] // Flatten (* Jean-François Alcover, Jan 21 2015, after Alois P. Heinz *)

A214159 Number of n X 3 nonconsecutive tableaux.

Original entry on oeis.org

1, 0, 1, 6, 72, 960, 14257, 228738, 3896062, 69590192, 1291977768, 24767357824, 487787117424, 9830929279248, 202119964701201, 4228355224663002, 89820746194643154, 1934075860467190608, 42153272431384984926, 928785495190695948612, 20666589509182675178064
Offset: 0

Views

Author

Alois P. Heinz, Jul 05 2012

Keywords

Comments

A standard Young tableau (SYT) where entries i and i+1 never appear in the same row is called a nonconsecutive tableau.

Examples

			a(2) = 1:
  [1 3 5]
  [2 4 6].
a(3) = 6:
  [1 4 7]   [1 3 7]   [1 4 6]   [1 3 6]   [1 3 6]   [1 3 5]
  [2 5 8]   [2 5 8]   [2 5 8]   [2 5 8]   [2 4 8]   [2 6 8]
  [3 6 9]   [4 6 9]   [3 7 9]   [4 7 9]   [5 7 9]   [4 7 9].
		

Crossrefs

Column k=3 of A214021.

Programs

  • Maple
    b:= proc(l, t) option remember; local n, s; n, s:= nops(l),
           add(i, i=l); `if`(s=0, 1, add(`if`(t<>i and l[i]>
          `if`(i=n, 0, l[i+1]), b(subsop(i=l[i]-1, l), i), 0), i=1..n))
        end:
    a:= n-> b([3$n], 0):
    seq(a(n), n=0..20);
    # second Maple program:
    a:= proc(n) option remember; `if`(n<3, [1, 0, 1][n+1],
          ((22120*n^5 -58226*n^4 +31547*n^3 +42158*n^2 -53589*n +16146)*a(n-1)
          -(5988 -27068*n +50360*n^2 -62154*n^3 +49630*n^4 -15400*n^5)*a(n-2)
          -(7560*n^5 -23058*n^4 +24333*n^3 -11976*n^2 +2967*n -306)*a(n-3))
          /(6*(n+2)*(140*n^2-357*n+234)*(n+1)^2))
        end:
    seq(a(n), n=0..25);
  • Mathematica
    b[l_, t_] := b[l, t] = Module[{n = Length[l], s = Total[l]}, If[s == 0, 1, Sum[If[t != i && l[[i]] > If[i == n, 0, l[[i + 1]]], b[ReplacePart[l, i -> l[[i]] - 1], i], 0], {i, 1, n}]]];
    a[n_] := b[Table[3, n], 0];
    Table[a[n], {n, 0, 20}] (* Jean-François Alcover, May 29 2018, from first Maple program *)

Formula

a(n) ~ 3^(3*n+13/2) / (2^12 * Pi * n^4). - Vaclav Kotesovec, Jul 16 2014

A214875 Number of 4 X n nonconsecutive tableaux.

Original entry on oeis.org

1, 1, 6, 72, 1289, 29889, 831174, 26455564, 934766625, 35896627737, 1475461220832, 64175536953702, 2928055871469177, 139180794974903769, 6854741942660442918, 348244986517582367748, 18183302860592129336633, 972820066413029570529513, 53192593416458179801289034
Offset: 0

Views

Author

Alois P. Heinz, Jul 28 2012

Keywords

Comments

A standard Young tableau (SYT) where entries i and i+1 never appear in the same row is called a nonconsecutive tableau.

Examples

			a(2) = 6:
  [1, 5]  [1, 4]  [1, 3]  [1, 4]  [1, 3]  [1, 3]
  [2, 6]  [2, 6]  [2, 6]  [2, 5]  [2, 5]  [2, 4]
  [3, 7]  [3, 7]  [4, 7]  [3, 7]  [4, 7]  [5, 7]
  [4, 8]  [5, 8]  [5, 8]  [6, 8]  [6, 8]  [6, 8].
		

Crossrefs

Row n=4 of A214021.

Programs

  • Maple
    a:= proc(n) option remember; `if`(n<3, [1,1,6][n+1], ((1620*n^7
           -13770*n^6 +41958*n^5 -48762*n^4 -6642*n^3 +62532*n^2 -48600*n
           +11664)*a(n-3) +(-3260*n^7 +11360*n^6 -4169*n^5 -19015*n^4
           +14521*n^3 +6179*n^2 -7380*n +1764)*a(n-2) +(-80*n +1964*n^3
           -7469*n^4 +3631*n^2 -5236*n^5 +2590*n^6 +1660*n^7 -300)*a(n-1))
           /((2*n+3)*(n+3)*(10*n^2-15*n-1)*(n+2)^3))
        end:
    seq(a(n), n=0..25);
  • Mathematica
    a[0] = a[1] = 1; a[2] = 6; a[n_] := a[n] = ((1620n^7 - 13770n^6 + 41958n^5 - 48762n^4 - 6642n^3 + 62532n^2 - 48600n + 11664) a[n-3] + (-3260n^7 + 11360n^6 - 4169n^5 - 19015n^4 + 14521n^3 + 6179n^2 - 7380n + 1764) a[n-2] + (-80n + 1964n^3 - 7469n^4 + 3631n^2 - 5236n^5 + 2590n^6 + 1660n^7 - 300) a[n-1])/((2n + 3)(n + 3)(10n^2 - 15n - 1)(n + 2)^3);
    Table[a[n], {n, 0, 25}] (* Jean-François Alcover, Jun 01 2018, from Maple *)

Formula

a(n) ~ 3^(4*n+12) / (2^13 * Pi^(3/2) * n^(15/2)). - Vaclav Kotesovec, Jul 16 2014

A264103 Number of n X n nonconsecutive tableaux.

Original entry on oeis.org

1, 1, 1, 6, 1289, 13652068, 11865331748843, 1232033659827201777222, 20955050449849509663209289613921, 76615072242390448445916336191834325715261848, 76456972050113830615729276134092575545874371011199394401950, 25770844284993968943713846068617488831241440984966512955013952234546614462044
Offset: 0

Views

Author

Alois P. Heinz, Nov 03 2015

Keywords

Comments

A standard Young tableau (SYT) where entries i and i+1 never appear in the same row is called a nonconsecutive tableau.

Examples

			a(3) = 6:
  [1 4 7]  [1 3 7]  [1 4 6]  [1 3 6]  [1 3 6]  [1 3 5]
  [2 5 8]  [2 5 8]  [2 5 8]  [2 5 8]  [2 4 8]  [2 6 8]
  [3 6 9]  [4 6 9]  [3 7 9]  [4 7 9]  [5 7 9]  [4 7 9].
		

Crossrefs

Main diagonal of A214021.

Programs

  • Mathematica
    b[l_, t_] := b[l, t] = Module[{n = Length[l], s = Total[l]}, If[s == 0, 1, Sum[If[t != i && l[[i]] > If[i == n, 0, l[[i+1]]], b[ReplacePart[l, i -> l[[i]]-1], i], 0], {i, 1, n}]]];
    a[n_] := a[n] = If[n<1, 1, b[Array[n&, n], 0]];
    Table[Print[n, " ", a[n]]; a[n], {n, 0, 11}] (* Jean-François Alcover, Sep 08 2021, after Alois P. Heinz in A214021 *)

Formula

a(n) = A214021(n,n).
Showing 1-6 of 6 results.