A306234
Number T(n,k) of occurrences of k in a (signed) displacement set of a permutation of [n] divided by |k|!; triangle T(n,k), n>=1, 1-n<=k<=n-1, read by rows.
Original entry on oeis.org
1, 1, 1, 1, 1, 3, 4, 3, 1, 1, 5, 13, 15, 13, 5, 1, 1, 7, 28, 67, 76, 67, 28, 7, 1, 1, 9, 49, 179, 411, 455, 411, 179, 49, 9, 1, 1, 11, 76, 375, 1306, 2921, 3186, 2921, 1306, 375, 76, 11, 1, 1, 13, 109, 679, 3181, 10757, 23633, 25487, 23633, 10757, 3181, 679, 109, 13, 1
Offset: 1
Triangle T(n,k) begins:
: 1 ;
: 1, 1, 1 ;
: 1, 3, 4, 3, 1 ;
: 1, 5, 13, 15, 13, 5, 1 ;
: 1, 7, 28, 67, 76, 67, 28, 7, 1 ;
: 1, 9, 49, 179, 411, 455, 411, 179, 49, 9, 1 ;
: 1, 11, 76, 375, 1306, 2921, 3186, 2921, 1306, 375, 76, 11, 1 ;
Columns k=0-10 give (offsets may differ):
A002467,
A180191,
A324352,
A324353,
A324354,
A324355,
A324356,
A324357,
A324358,
A324359,
A324360.
-
b:= proc(s, d) option remember; (n-> `if`(n=0, add(x^j, j=d),
add(b(s minus {i}, d union {n-i}), i=s)))(nops(s))
end:
T:= n-> (p-> seq(coeff(p, x, i)/abs(i)!, i=1-n..n-1))(b({$1..n}, {})):
seq(T(n), n=1..8);
# second Maple program:
T:= (n, k)-> -add((-1)^j*binomial(n-abs(k), j)*(n-j)!, j=1..n)/abs(k)!:
seq(seq(T(n, k), k=1-n..n-1), n=1..9);
-
T[n_, k_] := (-1/Abs[k]!) Sum[(-1)^j Binomial[n-Abs[k], j] (n-j)!, {j, 1, n}];
Table[T[n, k], {n, 1, 9}, {k, 1-n, n-1}] // Flatten (* Jean-François Alcover, Feb 15 2021 *)
A324362
Total number of occurrences of k in the (signed) displacement sets of all permutations of [n+k] divided by k!; square array A(n,k), n>=0, k>=0, read by antidiagonals.
Original entry on oeis.org
0, 0, 1, 0, 1, 1, 0, 1, 3, 4, 0, 1, 5, 13, 15, 0, 1, 7, 28, 67, 76, 0, 1, 9, 49, 179, 411, 455, 0, 1, 11, 76, 375, 1306, 2921, 3186, 0, 1, 13, 109, 679, 3181, 10757, 23633, 25487, 0, 1, 15, 148, 1115, 6576, 29843, 98932, 214551, 229384, 0, 1, 17, 193, 1707, 12151, 69299, 307833, 1006007, 2160343, 2293839
Offset: 0
Square array A(n,k) begins:
0, 0, 0, 0, 0, 0, 0, ...
1, 1, 1, 1, 1, 1, 1, ...
1, 3, 5, 7, 9, 11, 13, ...
4, 13, 28, 49, 76, 109, 148, ...
15, 67, 179, 375, 679, 1115, 1707, ...
76, 411, 1306, 3181, 6576, 12151, 20686, ...
455, 2921, 10757, 29843, 69299, 142205, 266321, ...
Columns k=0-10 give:
A002467,
A180191(n+1),
A324352,
A324353,
A324354,
A324355,
A324356,
A324357,
A324358,
A324359,
A324360.
-
A:= (n, k)-> -add((-1)^j*binomial(n, j)*(n+k-j)!, j=1..n)/k!:
seq(seq(A(n, d-n), n=0..d), d=0..12);
-
m = 10;
col[k_] := col[k] = CoefficientList[(1-Exp[-x])/(1-x)^(k+1)+O[x]^(m+1), x]* Range[0, m]!;
A[n_, k_] := col[k][[n+1]];
Table[A[n, d-n], {d, 0, m}, {n, 0, d}] // Flatten (* Jean-François Alcover, May 03 2021 *)
A207819
Number of permutations of [n] with a fixed point and/or a succession.
Original entry on oeis.org
0, 1, 1, 6, 20, 106, 618, 4358, 34836, 313592, 3135988, 34498646, 414007634, 5382362086, 75356174332, 1130382058576, 18086649408624, 307480839465174, 5534775895914982, 105162728081809146, 2103289132221173216, 44169707042511725964, 971745847021319655464, 22350404337704558809666, 536415027665581568375190, 13410494347081333360291850
Offset: 0
For n=4 the only permutations that do not count are 2143, 2413, 3142 and 4321, so a(4) = 4!-4 = 20.
-
F[{}] = 1; F[S_] := Sum[G[S ~Complement~ {s}, s-1], {s, S ~Complement~ {Length[S]}}];
G[{}, ] = 1; G[S, t_] := G[S, t] = Sum[G[S ~Complement~ {s}, s-1], {s, S ~Complement~ {t, Length[S]}}];
Table[a[n] = n! - F[Range[n]]; Print[n, " ", a[n]]; a[n], {n, 0, 20}] (* Jean-François Alcover, Mar 05 2019, using Robert Israel's code for A209322 *)
-
A207819(n)={my(p,c);sum(k=1,n!,p=numtoperm(n,k);(c=(p[1]==1)) || for(j=2,n,p[j]!=j & p[j]-1!=p[j-1] & next; c++; break);c)} \\ M. F. Hasler, Jan 13 2013
A207821
Number of permutations of [n] that either have a fixed point or a succession, but not both.
Original entry on oeis.org
0, 1, 0, 5, 12, 69, 370, 2609, 20552, 183249, 1817794, 19867793, 237126320, 3068483277, 42788761294, 639619513669, 10202914060472, 172984071549421, 3106257794721534, 58892020126278457, 1175554242034515780, 24643158882899363129, 541279064964716455230, 12431122899361840993737, 297944099946417376956220, 7439329384072966947792437
Offset: 0
a(4) = 12 because we have 1324, 1432, 2341, 2431, 3214, 3241, 3412, 3421, 4123, 4132, 4213 and 4312.
-
A207821(n)=my(p,c);sum(k=1,n!,p=numtoperm(n,k);c=(p[1]==1);for(j=2,n,p[j]==j & c<=0 & !c++ & break; p[j]-1==p[j-1] & c>=0 & !c-- & break); c!=0) \\ M. F. Hasler, Jan 13 2013
Values a(1) to a(10) double-checked by
M. F. Hasler, Jan 13 2013
A209322
Number of derangements of [n] with no succession.
Original entry on oeis.org
1, 0, 1, 0, 4, 14, 102, 682, 5484, 49288, 492812, 5418154, 64993966, 844658714, 11822116868, 177292309424, 2836140479376, 48206588630826, 867597809813018, 16482372327022854, 329612875955466784, 6921235129197714036, 152254880756288024536, 3501612401180417830334, 84033374067657870984810, 2100715696249652623708150
Offset: 0
For n=4 we have 2143, 2413, 3142 and 4321, so a(4) = 4.
-
F:= proc(S) add(G(S minus {s}, s-1), s = S minus {nops(S)}) end proc:
G:= proc(S,t) option remember;
if S = {} then return 1 fi;
add(procname(S minus {s},s-1), s = S minus {t, nops(S)})
end proc:
1,seq(F({$1..n}), n=1..19); # Robert Israel, Mar 02 2017
-
F[{}] = 1; F[S_] := Sum[G[S ~Complement~ {s}, s-1], {s, S ~Complement~ {Length[S]}}];
G[{}, ] = 1; G[S, t_] := G[S, t] = Sum[G[S ~Complement~ {s}, s-1], {s, S ~Complement~ {t, Length[S]}}];
Table[a[n] = F[Range[n]]; Print[n, " ", a[n]]; a[n], {n, 0, 20}] (* Jean-François Alcover, Mar 05 2019, after Robert Israel *)
-
{ a209322(n) = if(n==0, return(1)); my(A=matrix(n, n, i, j, i-j!=1 && i!=j)); parsum(s=1, 2^n-1, my(M=vecextract(A, s, s), d=matsize(M)[1], v=vectorv(d, i, 1), pos=bitand(s, 1)); if(pos, v[1]=0); for(k=1, n-1, v=M*v; if(bitand(s>>k, 1), v[pos++]=0)); (-1)^(n-d)*vecsum(v) ); } \\ Max Alekseyev, Apr 03 2025
A306461
Number T(n,k) of occurrences of k in a (signed) displacement set of a permutation of [n]; triangle T(n,k), n>=1, 1-n<=k<=n-1, read by rows.
Original entry on oeis.org
1, 1, 1, 1, 2, 3, 4, 3, 2, 6, 10, 13, 15, 13, 10, 6, 24, 42, 56, 67, 76, 67, 56, 42, 24, 120, 216, 294, 358, 411, 455, 411, 358, 294, 216, 120, 720, 1320, 1824, 2250, 2612, 2921, 3186, 2921, 2612, 2250, 1824, 1320, 720, 5040, 9360, 13080, 16296, 19086, 21514, 23633, 25487, 23633, 21514, 19086, 16296, 13080, 9360, 5040
Offset: 1
The 6 permutations p of [3]: 123, 132, 213, 231, 312, 321 have (signed) displacement sets {p(i)-i, i=1..3}: {0}, {-1,0,1}, {-1,0,1}, {-2,1}, {-1,2}, {-2,0,2}, respectively. Numbers -2 and 2 occur twice, -1 and 1 occur thrice, and 0 occurs four times. So row n=3 is [2, 3, 4, 3, 2].
Triangle T(n,k) begins:
: 1 ;
: 1, 1, 1 ;
: 2, 3, 4, 3, 2 ;
: 6, 10, 13, 15, 13, 10, 6 ;
: 24, 42, 56, 67, 76, 67, 56, 42, 24 ;
: 120, 216, 294, 358, 411, 455, 411, 358, 294, 216, 120 ;
-
b:= proc(s, d) option remember; (n-> `if`(n=0, add(x^j, j=d),
add(b(s minus {i}, d union {n-i}), i=s)))(nops(s))
end:
T:= n-> (p-> seq(coeff(p, x, i), i=1-n..n-1))(b({$1..n}, {})):
seq(T(n), n=1..8);
# second Maple program:
T:= (n, k)-> -add((-1)^j*binomial(n-abs(k), j)*(n-j)!, j=1..n):
seq(seq(T(n, k), k=1-n..n-1), n=1..9);
-
T[n_, k_] := -Sum[(-1)^j Binomial[n-Abs[k], j] (n-j)!, {j, 1, n}];
Table[Table[T[n, k], {k, 1-n, n-1}], {n, 1, 9}] // Flatten (* Jean-François Alcover, Feb 20 2021, after Alois P. Heinz *)
A276975
Number of permutations of [n] such that the minimal distance between elements of the same cycle equals one, a(1)=1 by convention.
Original entry on oeis.org
1, 1, 4, 19, 103, 651, 4702, 38413, 350559, 3539511, 39196758, 472612883, 6165080443, 86526834271, 1300282224846, 20832761552453, 354515666646827, 6386139146435035, 121406489336263622, 2429193186525638435, 51030147426536745655, 1122952442325988152627
Offset: 1
a(2) = 1: (1,2).
a(3) = 4: (1,2,3), (1,3,2), (1)(2,3), (1,2)(3).
-
b:= proc(n, i, l) option remember; `if`(n=0, mul(j!, j=l),
(m-> add(`if`(i=j, 0, b(n-1, j, `if`(j>m, [l[], 0],
subsop(j=l[j]+1, l)))), j=1..m+1))(nops(l)))
end:
a:= n-> `if`(n=1, 1, n!-b(n, 0, [])):
seq(a(n), n=1..15);
-
b[n_, i_, l_] := b[n, i, l] = If[n == 0, Product[j!, {j, l}], Function[m, Sum[If[i == j, 0, b[n - 1, j, If[j > m, Append[l, 0], ReplacePart[l, j -> l[[j]] + 1]]]], {j, 1, m + 1}]][Length[l]]];
a[n_] := If[n == 1, 1, n! - b[n, 0, {}]];
Array[a, 15] (* Jean-François Alcover, Oct 28 2020, after Maple code *)
A116853
Difference triangle of factorial numbers read by upward diagonals.
Original entry on oeis.org
1, 1, 2, 3, 4, 6, 11, 14, 18, 24, 53, 64, 78, 96, 120, 309, 362, 426, 504, 600, 720, 2119, 2428, 2790, 3216, 3720, 4320, 5040, 16687, 18806, 21234, 24024, 27240, 30960, 35280, 40320
Offset: 1
Starting with 1, 2, 6, 24, 120 ... we take the first difference row (A001563), second, third, etc. Reorient into a flush left format, getting:
[1] 1;
[2] 1, 2;
[3] 3, 4, 6;
[4] 11, 14, 18, 24;
[5] 53, 64, 78, 96, 120;
[6] 309, 362, 426, 504, 600, 720;
...
-
a116853 n k = a116853_tabl !! (n-1) !! (k-1)
a116853_row n = a116853_tabl !! (n-1)
a116853_tabl = map reverse $ f (tail a000142_list) [] where
f (u:us) vs = ws : f us ws where ws = scanl (-) u vs
-- Reinhard Zumkeller, Aug 31 2014
-
rows = 8;
rr = Range[rows]!;
dd = Table[Differences[rr, n], {n, 0, rows-1}];
T = Array[t, {rows, rows}];
Do[Thread[Evaluate[Diagonal[T, -k+1]] = dd[[k, ;;rows-k+1]]], {k, rows}];
Table[t[n, k], {n, 1, rows}, {k, 1, n}] // Flatten (* Jean-François Alcover, Dec 21 2019 *)
A209325
Number of permutations of [n] with a succession but no fixed points.
Original entry on oeis.org
0, 0, 0, 2, 5, 30, 163, 1172, 9349, 84208, 842149, 9266416, 111220875, 1446134218, 20248984181, 303774206310, 4860923772369, 82643503648838, 1487703851220935, 28268359232622252, 565401755237435337, 11874072125853230504, 261241878854832755345, 6008813069875360106928, 144216837237680799509479, 3605539586383814138649074
Offset: 0
For n=4 we have 2341, 3412, 3421, 4123 and 4312.
A209326
Number of permutations of [n] with a fixed point but no succession.
Original entry on oeis.org
0, 1, 0, 3, 7, 39, 207, 1437, 11203, 99041, 975645, 10601377, 125905445, 1622349059, 22539777113, 335845307359, 5341990288103, 90340567900583, 1618553943500599, 30623660893656205, 610152486797080443, 12769086757046132625, 280037186109883699885, 6422309829486480886809, 153727262708736577446741, 3833789797689152809143363
Offset: 0
For n=4 we have 1324, 1432, 2431, 3214, 3241, 4132 and 4213.
Showing 1-10 of 21 results.
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