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
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, ...
- Alois P. Heinz, Antidiagonals n = 0..21, 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(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$n], 0)):
seq(seq(A(n, d-n), n=0..d), d=0..14);
-
b[l_, t_] := b[l, t] = Module[{n, s}, {n, s} = {Length[l], Sum[i, {i, l}]};
If[s == 0, 1, Sum[If[t != i && Mod[s + i - l[[i]], 2] == 1 && l[[i]] > If[i == n, 0, l[[i+1]]], b[ReplacePart[l, {i -> l[[i]]-1}], i], 0], {i, 1, n}]] ]; a [n_, k_] := If[n < 1 || k < 1, 1, b[Array[k&, n], 0]]; Table[Table[a[n, d-n], {n, 0, d}], {d, 0, 14}] // Flatten (* Jean-François Alcover, Dec 11 2013, translated from Maple *)
A214021
Number A(n,k) of n X k nonconsecutive tableaux; square array A(n,k), n>=0, k>=0, read by antidiagonals.
Original entry on oeis.org
1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 0, 1, 1, 1, 1, 0, 1, 2, 1, 1, 1, 0, 1, 6, 6, 1, 1, 1, 0, 1, 22, 72, 18, 1, 1, 1, 0, 1, 92, 1289, 960, 57, 1, 1, 1, 0, 1, 422, 29889, 93964, 14257, 186, 1, 1, 1, 0, 1, 2074, 831174, 13652068, 8203915, 228738, 622, 1, 1
Offset: 0
A(2,4) = 1:
[1 3 5 7]
[2 4 6 8].
A(4,2) = 6:
[1, 5] [1, 4] [1, 3] [1, 4] [1, 3] [1, 3]
[2, 6] [2, 6] [2, 6] [2, 5] [2, 5] [2, 4]
[3, 7] [3, 7] [4, 7] [3, 7] [4, 7] [5, 7]
[4, 8] [5, 8] [5, 8] [6, 8] [6, 8] [6, 8].
Square array A(n,k) begins:
1, 1, 1, 1, 1, 1, 1, ...
1, 1, 0, 0, 0, 0, 0, ...
1, 1, 1, 1, 1, 1, 1, ...
1, 1, 2, 6, 22, 92, 422, ...
1, 1, 6, 72, 1289, 29889, 831174, ...
1, 1, 18, 960, 93964, 13652068, 2621897048, ...
1, 1, 57, 14257, 8203915, 8134044455, 11865331748843, ...
- Alois P. Heinz, Antidiagonals n = 0..23, flattened
- T. Y. Chow, H. Eriksson and C. K. Fan, Chess tableaux, Elect. J. Combin., 11 (2) (2005), #A3.
- S. Dulucq and O. Guibert, Stack words, standard tableaux and Baxter permutations, Disc. Math. 157 (1996), 91-106.
- Wikipedia, Young tableau
-
b:= proc(l, t) option remember; local n, s; n, s:= nops(l),
add(i, i=l); `if`(s=0, 1, add(`if`(t<>i and l[i]>
`if`(i=n, 0, l[i+1]), b(subsop(i=l[i]-1, l), i), 0), i=1..n))
end:
A:= (n, k)-> `if`(n<1 or k<1, 1, b([k$n], 0)):
seq(seq(A(n, d-n), n=0..d), d=0..12);
-
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 && 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, 12}] // Flatten (* Jean-François Alcover, Dec 09 2013, 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 *)
Showing 1-3 of 3 results.
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