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
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, ...
- Alois P. Heinz, Antidiagonals n = 0..24, flattened
- T. Y. Chow, H. Eriksson and C. K. Fan, Chess tableaux, Elect. J. Combin., 11 (2) (2005), #A3.
- Jonas Sjöstrand, On the sign-imbalance of partition shapes, arXiv:math/0309231v3 [math.CO], 2005.
- Wikipedia, Young tableau
-
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
-
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 *)
A214087
Sum of the squares of numbers of nonconsecutive tableaux over all partitions of n.
Original entry on oeis.org
1, 1, 1, 2, 6, 21, 92, 489, 3000, 20970, 166714, 1467337, 14212491, 149992662, 1723338952, 21393028409, 285061374438, 4054622024814, 61301381208116, 982904573560309, 16672187358390360, 298389960090957330, 5617735345244596804, 110942937545014894799
Offset: 0
-
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:
g:= (n, i, l)-> `if`(n=0 or i=1, b([l[], 1$n], 0)^2, `if`(i<1, 0,
add(g(n-i*j, i-1, [l[], i$j]), j=0..n/i))):
a:= n-> `if`(n<2, 1, g(n, n, [])):
seq(a(n), n=0..20);
-
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}]]];
g[n_, i_, l_] := If[n == 0 || i == 1, b[Join[l, Table[1, n]], 0]^2, If[i < 1, 0, Sum[g[n - i*j, i - 1, Join[l, Table[i, j]]], {j, 0, n/i}]]];
a[n_] := If[n < 2, 1, g[n, n, {}]]; Table[a[n], {n, 0, 20}] (* Jean-François Alcover, May 23 2018, translated from Maple *)
A238014
Number of chess tableaux with n cells.
Original entry on oeis.org
1, 1, 2, 2, 4, 6, 12, 20, 48, 84, 216, 408, 1104, 2280, 6288, 14128, 40256, 96240, 287904, 714016, 2246592, 5750112, 18900672, 49973568, 169592576, 466175808, 1618212224, 4637091200, 16393123072, 48926588544, 176264622336, 545058738944, 2008508679168
Offset: 0
a(5) = 6:
[1] [1 4] [1 2 3] [1 4 5] [1 2 3] [1 2 3 4 5]
[2] [2 5] [4] [2] [4 5]
[3] [3] [5] [3]
[4]
[5]
Note how the tableaux become partial chessboards when reduced modulo 2:
[1] [1 0] [1 0 1] [1 0 1] [1 0 1] [1 0 1 0 1]
[0] [0 1] [0] [0] [0 1]
[1] [1] [1] [1]
[0]
[1]
From _Joerg Arndt_, Feb 28 2014: (Start)
The a(7) = 20 ballot sequences are (dots for zeros):
01: [ . . . . . . . ]
02: [ . . . . . 1 1 ]
03: [ . . . . . 1 2 ]
04: [ . . . 1 1 . . ]
05: [ . . . 1 1 . 2 ]
06: [ . . . 1 1 1 2 ]
07: [ . . . 1 2 . . ]
08: [ . . . 1 2 . 1 ]
09: [ . . . 1 2 3 1 ]
10: [ . . . 1 2 3 4 ]
11: [ . 1 2 . . . . ]
12: [ . 1 2 . . . 1 ]
13: [ . 1 2 . . 3 1 ]
14: [ . 1 2 . . 3 4 ]
15: [ . 1 2 . 1 2 . ]
16: [ . 1 2 . 1 3 . ]
17: [ . 1 2 . 1 3 4 ]
18: [ . 1 2 3 4 . . ]
19: [ . 1 2 3 4 . 1 ]
20: [ . 1 2 3 4 5 6 ]
(End)
- Alois P. Heinz, Table of n, a(n) for n = 0..58
- T. Y. Chow, H. Eriksson and C. K. Fan, Chess tableaux, Elect. J. Combin., 11 (2) (2005), #A3.
- Jonas Sjöstrand, On the sign-imbalance of partition shapes, arXiv:math/0309231v3 [math.CO], 2005.
- Wikipedia, Young tableau
-
b:= proc() option remember; local s; s:= add(i, i=args); `if`(s=0, 1,
`if`(args[nargs]=0, b(subsop(nargs=NULL, [args])[]),
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:
g:= (n, i, l)-> `if`(n=0 or i=1, b(l[], 1$n), `if`(i<1, 0,
add(g(n-i*j, i-1, [l[], i$j]), j=0..n/i))):
a:= n-> g(n, n, []):
seq(a(n), n=0..32);
-
b[args_] := b[args] = Module[{nargs = Length[args], s = Total[args]}, If[s == 0, 1, If[Last[args] == 0, b[Most[args]], Sum[If[Mod[s + i - args[[i]], 2] == 1 && args[[i]] > If[i == nargs, 0, args[[i + 1]]], b[Append[ ReplacePart[ args, i -> args[[i]] - 1], 0]], 0], {i, 1, nargs}]]]];
g[n_, i_, l_] := g[n, i, l] = If[n == 0 || i == 1, b[Join[l, Table[1, n]]], If[i < 1, 0, Sum[g[n - i*j, i - 1, Join[l, Table[i, j]]], {j, 0, n/i}]]];
a[n_] := g[n, n, {}];
Table[a[n], {n, 0, 32}] (* Jean-François Alcover, Nov 14 2017, after Alois P. Heinz *)
A238184
Sum of the squares of numbers of nonconsecutive chess tableaux over all partitions of n.
Original entry on oeis.org
1, 1, 1, 1, 2, 2, 4, 7, 16, 37, 107, 282, 1020, 2879, 12507, 39347, 179231, 687974, 3225246, 14955561, 75999551, 392585613, 2271201137, 12183159188, 81562521256, 446611878413, 3336304592155, 19202329389234, 152803821604669, 958953289839930, 7835058287650579
Offset: 0
a(7) = 1 + 2^2 + 1 + 1 = 7:
.
: [1111111] : [22111] : [3211] : [322] : <- shapes
:-----------+--------------+---------+---------:
: [1] : [1 6] [1 4] : [1 4 7] : [1 4 7] :
: [2] : [2 7] [2 5] : [2 5] : [2 5] :
: [3] : [3] [3] : [3] : [3 6] :
: [4] : [4] [6] : [6] : :
: [5] : [5] [7] : : :
: [6] : : : :
: [7] : : : :
- Alois P. Heinz, Table of n, a(n) for n = 0..50
- T. Y. Chow, H. Eriksson and C. K. Fan, Chess tableaux, Elect. J. Combin., 11 (2) (2005), #A3.
- Jonas Sjöstrand, On the sign-imbalance of partition shapes, arXiv:math/0309231v3 [math.CO], 2005.
- Wikipedia, Young tableau
-
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=`if`(i=n and l[n]=1, [][], l[i]-1), l), i), 0), i=1..n))
end:
g:= (n, i, l)-> `if`(n=0 or i=1, b([l[], 1$n], 0)^2, `if`(i<1, 0,
add(g(n-i*j, i-1, [l[], i$j]), j=0..n/i))):
a:= n-> g(n, n, []):
seq(a(n), n=0..32);
-
b[l_, t_] := b[l, t] = Module[{n, s}, {n, s} = {Length[l], Total[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 -> If[i==n && l[[n]]==1, Nothing, l[[i]]-1]], i], 0], {i, 1, n}]]]; g[n_, i_, l_] := g[n, i, l] = If[n==0 || i==1, b[Join[l, Array[1&, n]], 0]^2, If[i<1, 0, Sum[g[n-i*j, i-1, Join[l, Array[i&, j]]], {j, 0, n/i}]]]; a[n_] := g[n, n, {}]; Table[a[n], {n, 0, 32}] (* Jean-François Alcover, Feb 17 2017, translated from Maple *)
Showing 1-4 of 4 results.
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