A080510
Triangle read by rows: T(n,k) gives the number of set partitions of {1,...,n} with maximum block length k.
Original entry on oeis.org
1, 1, 1, 1, 3, 1, 1, 9, 4, 1, 1, 25, 20, 5, 1, 1, 75, 90, 30, 6, 1, 1, 231, 420, 175, 42, 7, 1, 1, 763, 2016, 1015, 280, 56, 8, 1, 1, 2619, 10024, 6111, 1890, 420, 72, 9, 1, 1, 9495, 51640, 38010, 12978, 3150, 600, 90, 10, 1, 1, 35695, 276980, 244035, 91938, 24024, 4950, 825, 110, 11, 1
Offset: 1
T(4,3) = 4 since there are 4 set partitions with longest block of length 3: {{1},{2,3,4}}, {{1,3,4},{2}}, {{1,2,3},{4}} and {{1,2,4},{3}}.
Triangle begins:
1;
1, 1;
1, 3, 1;
1, 9, 4, 1;
1, 25, 20, 5, 1;
1, 75, 90, 30, 6, 1;
1, 231, 420, 175, 42, 7, 1;
1, 763, 2016, 1015, 280, 56, 8, 1;
1, 2619, 10024, 6111, 1890, 420, 72, 9, 1;
...
Cf.
A157396,
A157397,
A157398,
A157399,
A157400,
A157401,
A157402,
A157403,
A157404,
A157405. -
Peter Luschny, Mar 09 2009
Columns k=1..10 give:
A000012 (for n>0),
A001189,
A229245,
A229246,
A229247,
A229248,
A229249,
A229250,
A229251,
A229252. -
Alois P. Heinz, Sep 17 2013
-
b:= proc(n, i) option remember; `if`(n=0, 1, `if`(i<1, 0,
add(b(n-i*j, i-1) *n!/i!^j/(n-i*j)!/j!, j=0..n/i)))
end:
T:= (n, k)-> b(n, k) -b(n, k-1):
seq(seq(T(n, k), k=1..n), n=1..12); # Alois P. Heinz, Apr 20 2012
-
<< DiscreteMath`NewCombinatorica`; Table[Length/@Split[Sort[Max[Length/@# ]&/@SetPartitions[n]]], {n, 12}]
(* Second program: *)
b[n_, i_] := b[n, i] = If[n == 0, 1, If[i<1, 0, Sum[b[n-i*j, i-1]*n!/i!^j/(n-i*j)!/j!, {j, 0, n/i}]]]; T[n_, k_] := b[n, k]-b[n, k-1]; Table[Table[T[n, k], {k, 1, n}], {n, 1, 12}] // Flatten (* Jean-François Alcover, Feb 25 2014, after Alois P. Heinz *)
A276921
Number A(n,k) of ordered set partitions of [n] with at most k elements per block; 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, 6, 0, 1, 1, 3, 12, 24, 0, 1, 1, 3, 13, 66, 120, 0, 1, 1, 3, 13, 74, 450, 720, 0, 1, 1, 3, 13, 75, 530, 3690, 5040, 0, 1, 1, 3, 13, 75, 540, 4550, 35280, 40320, 0, 1, 1, 3, 13, 75, 541, 4670, 45570, 385560, 362880, 0
Offset: 0
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, 6, 12, 13, 13, 13, 13, 13, ...
0, 24, 66, 74, 75, 75, 75, 75, ...
0, 120, 450, 530, 540, 541, 541, 541, ...
0, 720, 3690, 4550, 4670, 4682, 4683, 4683, ...
0, 5040, 35280, 45570, 47110, 47278, 47292, 47293, ...
Columns k=0..10 give:
A000007,
A000142,
A080599,
A189886,
A276924,
A276925,
A276926,
A276927,
A276928,
A276929,
A276930.
-
A:= proc(n, k) option remember; `if`(n=0, 1, add(
A(n-i, k)*binomial(n, i), i=1..min(n, k)))
end:
seq(seq(A(n, d-n), n=0..d), d=0..12);
-
A[n_, k_] := A[n, k] = If[n==0, 1, Sum[A[n-i, k]*Binomial[n, i], {i, 1, Min[n, k]}]]; Table[A[n, d-n], {d, 0, 12}, {n, 0, d}] // Flatten (* Jean-François Alcover, Feb 03 2017, translated from Maple *)
A335508
Number of patterns of length n matching the pattern (1,1,1).
Original entry on oeis.org
0, 0, 0, 1, 9, 91, 993, 12013, 160275, 2347141, 37496163, 649660573, 12142311195, 243626199181, 5224710549243, 119294328993853, 2889836999693355, 74037381200415901, 2000383612949821323, 56850708386783835133, 1695491518035158123115, 52949018580275965241821
Offset: 0
The a(3) = 1 through a(4) = 9 patterns:
(1,1,1) (1,1,1,1)
(1,1,1,2)
(1,1,2,1)
(1,2,1,1)
(1,2,2,2)
(2,1,1,1)
(2,1,2,2)
(2,2,1,2)
(2,2,2,1)
The complement
A080599 is the avoiding version.
Permutations of prime indices matching this pattern are counted by
A335510.
Compositions matching this pattern are counted by
A335455 and ranked by
A335512.
Patterns matching the pattern (1,1) are counted by
A019472.
Combinatory separations are counted by
A269134.
Patterns matched by standard compositions are counted by
A335454.
Minimal patterns avoided by a standard composition are counted by
A335465.
Patterns matching (1,2,3) are counted by
A335515.
Cf.
A034691,
A056986,
A232464,
A238279,
A292884,
A333175,
A333755,
A335451,
A335456,
A335457,
A335458.
-
b:= proc(n, k) option remember; `if`(n=0, 1, add(
b(n-i, k)*binomial(n, i), i=1..min(n, k)))
end:
a:= n-> b(n$2)-b(n, 2):
seq(a(n), n=0..21); # Alois P. Heinz, Jan 28 2024
-
allnorm[n_]:=If[n<=0,{{}},Function[s,Array[Count[s,y_/;y<=#]+1&,n]]/@Subsets[Range[n-1]+1]];
Table[Length[Select[Join@@Permutations/@allnorm[n],MatchQ[#,{_,x_,_,x_,_,x_,_}]&]],{n,0,6}]
A276923
Number of ordered set partitions of [2n] where the maximal block size equals n.
Original entry on oeis.org
1, 2, 42, 860, 21490, 657972, 24011988, 1017804216, 49118959890, 2657929522820, 159340977018652, 10480673825750856, 750335572490293972, 58077997318270046600, 4832536579295065540200, 430136064463753547944560, 40779223639911413185024530
Offset: 0
-
A:= proc(n, k) option remember; `if`(n=0, 1, add(
A(n-i, k)*binomial(n, i), i=1..min(n, k)))
end:
a:= n-> A(2*n, n) -`if`(n=0, 0, A(2*n, n-1)):
seq(a(n), n=0..20);
-
A[n_, k_] := A[n, k] = If[n == 0, 1, Sum[A[n - i, k]*Binomial[n, i], {i, 1, Min[n, k]}]];
a[n_] := A[2*n, n] - If[n == 0, 0, A[2*n, n - 1]];
Table[a[n], {n, 0, 20}] (* Jean-François Alcover, Jun 13 2018, translated from Maple *)
A320758
Number of ordered set partitions of [n] where the maximal block size equals two.
Original entry on oeis.org
1, 6, 42, 330, 2970, 30240, 345240, 4377240, 61122600, 933055200, 15470254800, 277005128400, 5329454130000, 109681187616000, 2404894892400000, 55977698400624000, 1378748676601296000, 35829233832135744000, 979763376201049440000, 28124715476056399200000
Offset: 2
-
b:= proc(n, k) option remember; `if`(n=0, 1, add(
b(n-i, k)*binomial(n, i), i=1..min(n, k)))
end:
a:= n-> (k-> b(n, k) -b(n, k-1))(2):
seq(a(n), n=2..25);
-
b[n_, k_] := b[n, k] = If[n == 0, 1, Sum[b[n - i, k] Binomial[n, i], {i, 1, Min[n, k]}]];
a[n_] := With[{k = 2}, b[n, k] - b[n, k-1]];
a /@ Range[2, 25] (* Jean-François Alcover, Dec 14 2020, after Alois P. Heinz *)
A320759
Number of ordered set partitions of [n] where the maximal block size equals three.
Original entry on oeis.org
1, 8, 80, 860, 10290, 136080, 1977360, 31365600, 539847000, 10026139200, 199937337600, 4262167509600, 96744738090000, 2329950823200000, 59348032327584000, 1594257675506496000, 45047749044458160000, 1335740755933584000000, 41473196779273459200000
Offset: 3
-
b:= proc(n, k) option remember; `if`(n=0, 1, add(
b(n-i, k)*binomial(n, i), i=1..min(n, k)))
end:
a:= n-> (k-> b(n, k) -b(n, k-1))(3):
seq(a(n), n=3..25);
-
b[n_, k_] := b[n, k] = If[n == 0, 1, Sum[b[n - i, k] Binomial[n, i], {i, 1, Min[n, k]}]];
a[n_] := With[{k = 3}, b[n, k] - b[n, k-1]];
a /@ Range[3, 25] (* Jean-François Alcover, Dec 14 2020, after Alois P. Heinz *)
A320760
Number of ordered set partitions of [n] where the maximal block size equals four.
Original entry on oeis.org
1, 10, 120, 1540, 21490, 326970, 5402250, 96500250, 1855334250, 38228190000, 840776937000, 19666511865000, 487617137007000, 12776791730703000, 352825452012033000, 10242418813814187000, 311854958169459705000, 9937942309809373860000, 330821844137019184950000
Offset: 4
-
b:= proc(n, k) option remember; `if`(n=0, 1, add(
b(n-i, k)*binomial(n, i), i=1..min(n, k)))
end:
a:= n-> (k-> b(n, k) -b(n, k-1))(4):
seq(a(n), n=4..25);
-
b[n_, k_] := b[n, k] = If[n == 0, 1, Sum[b[n - i, k] Binomial[n, i], {i, 1, Min[n, k]}]];
a[n_] := With[{k = 4}, b[n, k] - b[n, k-1]];
a /@ Range[4, 25] (* Jean-François Alcover, Dec 14 2020, after Alois P. Heinz *)
A320761
Number of ordered set partitions of [n] where the maximal block size equals five.
Original entry on oeis.org
1, 12, 168, 2464, 38808, 657972, 11997216, 234594360, 4903616718, 109205019924, 2582909885556, 64686057980544, 1710536977653504, 47637803779229664, 1393903719674129664, 42758329987344875904, 1372254504736418142840, 45989719374155059863360
Offset: 5
-
b:= proc(n, k) option remember; `if`(n=0, 1, add(
b(n-i, k)*binomial(n, i), i=1..min(n, k)))
end:
a:= n-> (k-> b(n, k) -b(n, k-1))(5):
seq(a(n), n=5..25);
-
b[n_, k_] := b[n, k] = If[n == 0, 1, Sum[b[n - i, k] Binomial[n, i], {i, 1, Min[n, k]}]];
a[n_] := With[{k = 5}, b[n, k] - b[n, k-1]];
a /@ Range[5, 25] (* Jean-François Alcover, Dec 14 2020, after Alois P. Heinz *)
A320762
Number of ordered set partitions of [n] where the maximal block size equals six.
Original entry on oeis.org
1, 14, 224, 3696, 64680, 1206744, 24011988, 508864356, 11459682234, 273563089800, 6904861371408, 183819838041840, 5149305370473264, 151447801937560128, 4666989813249123360, 150394712706368466336, 5059062167993588722968, 177346570951333803395376
Offset: 6
-
b:= proc(n, k) option remember; `if`(n=0, 1, add(
b(n-i, k)*binomial(n, i), i=1..min(n, k)))
end:
a:= n-> (k-> b(n, k) -b(n, k-1))(6):
seq(a(n), n=6..25);
A320763
Number of ordered set partitions of [n] where the maximal block size equals seven.
Original entry on oeis.org
1, 16, 288, 5280, 101640, 2068704, 44595408, 1017804216, 24559319070, 625388375040, 16772475939648, 472802783660064, 13981054231585584, 432866241024085440, 14006847775868101440, 472893544571144089536, 16631451859811919417144, 608402197372214335559040
Offset: 7
-
b:= proc(n, k) option remember; `if`(n=0, 1, add(
b(n-i, k)*binomial(n, i), i=1..min(n, k)))
end:
a:= n-> (k-> b(n, k) -b(n, k-1))(7):
seq(a(n), n=7..25);
Showing 1-10 of 13 results.
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