A328357
Number of inversion sequences of length n avoiding the consecutive patterns 000, 001, 011, 012.
Original entry on oeis.org
1, 1, 2, 1, 4, 6, 36, 117, 804, 4266, 33768, 249144, 2289348, 21353472, 227212824, 2533824900, 30914509212, 398623158096, 5508014798052, 80377645583430, 1242697826967816, 20218588415853480, 346035438765576720, 6206862951272939550, 116518581654518098332
Offset: 0
The a(4)=4 length 4 inversion sequences avoiding the consecutive patterns 000, 001, 011, 012 are 0100, 0101, 0102, 0103.
The a(5)=6 length 5 inversion sequences are 01010, 01020, 01021, 01030, 01031, 01032.
Cf.
A328358,
A328429,
A328430,
A328431,
A328432,
A328433,
A328434,
A328435,
A328436,
A328437,
A328438,
A328439,
A328440,
A328441,
A328442.
-
b:= proc(n, x, t) option remember; `if`(n=0, 1, add(
`if`(t and i<=x, 0, b(n-1, i, i<=x)), i=1..n))
end:
a:= n-> b(n, 0, false):
seq(a(n), n=0..24); # Alois P. Heinz, Oct 14 2019
-
b[n_, x_, t_] := b[n, x, t] = If[n == 0, 1, Sum[If[t && i <= x, 0, b[n - 1, i, i <= x]], {i, 1, n}]];
a[n_] := b[n, 0, False];
a /@ Range[0, 24] (* Jean-François Alcover, Feb 25 2020, after Alois P. Heinz *)
A328358
Number of inversion sequences of length n avoiding the consecutive patterns 012, 021, 010, 120.
Original entry on oeis.org
1, 1, 2, 4, 10, 30, 100, 376, 1566, 7094, 34751, 182841, 1026167, 6112799, 38489481, 255204077, 1776046697, 12936265145, 98368170749, 779127467795, 6414876317675, 54802126603135, 484967246285755, 4438877330941077, 41963817964950737, 409224941931240185
Offset: 0
The length 4 inversion sequences avoiding the consecutive patterns 012, 021, 010, 120 are 0000, 0110, 0001, 0011, 0111, 0002, 0112, 0022, 0003, 0113.
Cf.
A328357,
A328429,
A328430,
A328431,
A328432,
A328433,
A328434,
A328435,
A328436,
A328437,
A328438,
A328439,
A328440,
A328441,
A328442.
-
b:= proc(n, x, t, c) option remember; `if`(n=0, 1, add(`if`(ix, max(0, c-1))), i=1..n))
end:
a:= n-> b(n, 0, false, 2):
seq(a(n), n=0..25); # Alois P. Heinz, Oct 14 2019
-
b[n_, x_, t_, c_] := b[n, x, t, c] = If[n == 0, 1, Sum[If[i < x && t && c == 0, 0, b[n - 1, i, i != x, Max[0, c - 1]]], {i, 1, n}]];
a[n_] := b[n, 0, False, 2];
a /@ Range[0, 25] (* Jean-François Alcover, Mar 01 2020, after Alois P. Heinz *)
A328441
Number of inversion sequences of length n avoiding the consecutive pattern 100.
Original entry on oeis.org
1, 1, 2, 6, 23, 109, 618, 4098, 31173, 267809, 2565520, 27120007, 313616532, 3938508241, 53381045786, 776672993274, 12074274033482, 199746500391688, 3503656507826887, 64951437702821877, 1268898555348831913, 26055882443142671038, 561050228044941209930, 12641053014560238560492, 297439800300471548183778
Offset: 0
Note that a(4)=23. Indeed, of the 24 inversion sequences of length 4, the only one that does not avoid the consecutive pattern 100 is 0100.
Similarly, 0110 is the only inversion sequence of length 4 that does not avoid the consecutive pattern 110.
- Vaclav Kotesovec, Table of n, a(n) for n = 0..448
- Juan S. Auli, Pattern Avoidance in Inversion Sequences, Ph. D. thesis, Dartmouth College, ProQuest Dissertations Publishing (2020), 27964164.
- Juan S. Auli and Sergi Elizalde, Consecutive Patterns in Inversion Sequences, arXiv:1904.02694 [math.CO], 2019.
- Juan S. Auli and Sergi Elizalde, Consecutive patterns in inversion sequences II: avoiding patterns of relations, arXiv:1906.07365 [math.CO], 2019.
- Juan S. Auli and Sergi Elizalde, Wilf equivalences between vincular patterns in inversion sequences, arXiv:2003.11533 [math.CO], 2020.
Cf.
A328357,
A328358,
A328429,
A328430,
A328431,
A328432,
A328433,
A328434,
A328435,
A328436,
A328437,
A328438,
A328439,
A328440,
A328442
-
# after Alois P. Heinz in A328357
b := proc(n, x, t) local i; option remember; `if`(n = 0, 1, add(`if`(t and x < i, 0, b(n - 1, i, i = x)), i = 0 .. n - 1)); end proc;
a := n -> b(n, -1, false);
seq(a(n), n = 0 .. 24);
-
i100[1] = 1; i100[2] = 2; i100[n_] := i100[n] = Sum[s100[n, k], {k, 0, n - 1}]; s100[n_, k_] := s100[n, k] = i100[n - 1] - Sum[s100[n - 2, j], {j, k + 1, n - 3}]; Flatten[{1, Table[i100[m], {m, 1, 25}]}] (* Vaclav Kotesovec, Oct 18 2019 *)
A328433
Number of inversion sequences of length n avoiding the consecutive patterns 011 and 012.
Original entry on oeis.org
1, 1, 2, 4, 11, 37, 157, 791, 4676, 31490, 238814, 2009074, 18585645, 187366675, 2045016693, 24018394333, 302051731428, 4049206907012, 57642586053512, 868375941780450, 13801973373609889, 230808858283551859, 4051069379668626948, 74459335679007458268
Offset: 0
The a(4)=11 length 4 inversion sequences avoiding the consecutive patterns 011 and 012 are 0000, 0100, 0010, 0020, 0001, 0101, 0021, 0002, 0102, 0003, and 0103.
Cf.
A328357,
A328358,
A328429,
A328430,
A328431,
A328432,
A328434,
A328435,
A328436,
A328437,
A328438,
A328439,
A328440,
A328441,
A328442.
-
# after Alois P. Heinz in A328357
b := proc(n, x, t) option remember; `if`(n = 0, 1, add(
`if`(t and i < x, 0, b(n - 1, i, i <= x)), i = 0 .. n - 1))
end proc:
a := n -> b(n, -1, false):
seq(a(n), n = 0 .. 24);
-
b[n_, x_, t_] := b[n, x, t] = If[n == 0, 1, Sum[If[t && i < x, 0, b[n - 1, i, i <= x]], {i, 0, n - 1}]];
a[n_] := b[n, -1, False];
a /@ Range[0, 24] (* Jean-François Alcover, Mar 02 2020, after Alois P. Heinz in A328357 *)
A328437
Number of inversion sequences of length n avoiding the consecutive pattern 001.
Original entry on oeis.org
1, 1, 2, 4, 11, 42, 210, 1292, 9352, 77505, 722294, 7470003, 84854788, 1049924370, 14052654158, 202271440732, 3115338658280, 51118336314648, 890201500701303, 16397264064993185, 318505677099378561, 6506565509515408206, 139449260758011488550, 3128599281190613701180
Offset: 0
The a(4)=11 length 4 inversion sequences avoiding the consecutive pattern 001 are 0000, 0100, 0110, 0120, 0101, 0111, 0121, 0102, 0122, 0103, and 0123.
- Vaclav Kotesovec, Table of n, a(n) for n = 0..448
- Juan S. Auli, Pattern Avoidance in Inversion Sequences, Ph. D. thesis, Dartmouth College, ProQuest Dissertations Publishing (2020), 27964164.
- Juan S. Auli and Sergi Elizalde, Consecutive Patterns in Inversion Sequences, arXiv:1904.02694 [math.CO], 2019.
- Juan S. Auli and Sergi Elizalde, Consecutive patterns in inversion sequences II: avoiding patterns of relations, arXiv:1906.07365 [math.CO], 2019.
Cf.
A328357,
A328358,
A328429,
A328430,
A328431,
A328432,
A328433,
A328434,
A328435,
A328436,
A328438,
A328439,
A328440,
A328441,
A328442.
-
# after Alois P. Heinz in A328357
b := proc(n, x, t) option remember; `if`(n = 0, 1, add(
`if`(t and i = x, 0, b(n - 1, i, i < x)), i = 0 .. n - 1))
end proc:
a := n -> b(n, -1, false):
seq(a(n), n = 0 .. 24);
-
b[n_, x_, t_] := b[n, x, t] = If[n == 0, 1, Sum[If[t && i == x, 0, b[n - 1, i, i < x]], {i, 0, n - 1}]];
a[n_] := b[n, -1, False];
a /@ Range[0, 24] (* Jean-François Alcover, Mar 02 2020, after Alois P. Heinz in A328357 *)
A328439
Number of inversion sequences of length n avoiding the consecutive pattern 011.
Original entry on oeis.org
1, 1, 2, 5, 17, 75, 407, 2621, 19524, 165090, 1561900, 16345264, 187452475, 2337729329, 31497068553, 455930417721, 7056447326642, 116279714536838, 2032547040624336, 37563420959431569, 731810131489893185, 14989602024463575408, 322032777284323744894, 7240745954488939549295
Offset: 0
The a(4)=17 length 4 inversion sequences avoiding the consecutive pattern 011 are 0000, 0100, 0010, 0020, 0120, 0001, 0101, 0021, 0121, 0002, 0102, 0012, 0003, 0103, 0013, 0023, and 0123.
- Vaclav Kotesovec, Table of n, a(n) for n = 0..448
- Juan S. Auli, Pattern Avoidance in Inversion Sequences, Ph. D. thesis, Dartmouth College, ProQuest Dissertations Publishing (2020), 27964164.
- Juan S. Auli and Sergi Elizalde, Consecutive Patterns in Inversion Sequences, arXiv:1904.02694 [math.CO], 2019.
- Juan S. Auli and Sergi Elizalde, Consecutive patterns in inversion sequences II: avoiding patterns of relations, arXiv:1906.07365 [math.CO], 2019.
Cf.
A328357,
A328358,
A328429,
A328430,
A328431,
A328432,
A328433,
A328434,
A328435,
A328436,
A328437,
A328438,
A328440,
A328441,
A328442.
-
# after Alois P. Heinz in A328357
b := proc(n, x, t) option remember; `if`(n = 0, 1, add(
`if`(t and i < x, 0, b(n - 1, i, i = x)), i = 0 .. n - 1))
end proc:
a := n -> b(n, -1, false):
seq(a(n), n = 0 .. 24);
-
b[n_, x_, t_] := b[n, x, t] = If[n == 0, 1, Sum[If[t && i < x, 0, b[n - 1, i, i == x]], {i, 0, n - 1}]];
a[n_] := b[n, -1, False];
a /@ Range[0, 24] (* Jean-François Alcover, Mar 02 2020, after Alois P. Heinz in A328357 *)
A328442
Number of inversion sequences of length n avoiding the consecutive pattern 210.
Original entry on oeis.org
1, 1, 2, 6, 24, 118, 684, 4554, 34192, 285558, 2624496, 26315990, 285828324, 3342566724, 41869664320, 559265742918, 7934746600620, 119162454310392, 1888417811354292, 31492626988890798, 551302582228438512, 10107905106374914860, 193700015975819881008, 3872391687779493752340, 80623321999146782133372
Offset: 0
Note that a(5)=118. Indeed, of the 120 inversion sequences of length 5, the only ones that do not avoid the consecutive patterns 210 are 00210 and 01210.
- Vaclav Kotesovec, Table of n, a(n) for n = 0..460
- Juan S. Auli, Pattern Avoidance in Inversion Sequences, Ph. D. thesis, Dartmouth College, ProQuest Dissertations Publishing (2020), 27964164.
- Juan S. Auli and Sergi Elizalde, Consecutive Patterns in Inversion Sequences, arXiv:1904.02694 [math.CO], 2019.
- Juan S. Auli and Sergi Elizalde, Consecutive patterns in inversion sequences II: avoiding patterns of relations, arXiv:1906.07365 [math.CO], 2019.
Cf.
A328357,
A328358,
A328429,
A328430,
A328431,
A328432,
A328433,
A328434,
A328435,
A328436,
A328437,
A328438,
A328439,
A328440,
A328441.
-
# after Alois P. Heinz in A328357
b := proc(n, x, t) option remember; `if`(n = 0, 1, add(
`if`(t and x < i, 0, b(n - 1, i, x < i)), i = 0 .. n - 1))
end proc:
a := n -> b(n, n, false):
seq(a(n), n = 0 .. 24);
-
b[n_, x_, t_] := b[n, x, t] = If[n == 0, 1, Sum[If[t && x < i, 0, b[n - 1, i, x < i]], {i, 0, n - 1}]];
a[n_] := b[n, n, False];
a /@ Range[0, 24] (* Jean-François Alcover, Mar 02 2020, after Alois P. Heinz in A328357 *)
A328429
Number of inversion sequences of length n avoiding the consecutive patterns 012, 101, 102, and 201.
Original entry on oeis.org
1, 1, 2, 5, 14, 46, 170, 691, 3073, 14809, 76666, 423886, 2490514, 15479614, 101389508, 697513653, 5025406212, 37819960947, 296618360520, 2419362514273, 20484053318220, 179723185666151, 1631519158000420, 15302546831928727, 148099068509673563
Offset: 0
The a(4)=14 length 4 inversion sequences avoiding the consecutive patterns 012, 101, 102, and 201 are 0000, 0100, 0010, 0110, 0020, 0001, 0011, 0111, 0021, 0002, 0112, 0022, 0003, and 0113.
Cf.
A328357,
A328358,
A328430,
A328431,
A328432,
A328433,
A328434,
A328435,
A328436,
A328437,
A328438,
A328439,
A328440,
A328441,
A328442.
-
# after Alois P. Heinz in A328357
b := proc(n, x, t) option remember; `if`(n = 0, 1, add(
`if`(t and i <> x, 0, b(n-1, i, i b(n, -1, false):
seq(a(n), n = 0 .. 24);
-
b[n_, x_, t_] := b[n, x, t] = If[n == 0, 1, Sum[If[t && i != x, 0, b[n - 1, i, i < x]], {i, 0, n - 1}]];
a[n_] := b[n, -1, False];
a /@ Range[0, 24] (* Jean-François Alcover, Mar 02 2020 after Alois P. Heinz in A328357 *)
A328430
Number of inversion sequences of length n avoiding the consecutive patterns 001 and 012.
Original entry on oeis.org
1, 1, 2, 3, 7, 18, 70, 317, 1825, 11805, 88212, 727731, 6660103, 66377942, 718681969, 8376682083, 104703957902, 1395883946839, 19777652272297, 296686846198829, 4697959440255354, 78299282813403618, 1370127872827224359, 25114095425698971152, 481202765468970358153
Offset: 0
The a(4)=7 length 4 inversion sequences avoiding the consecutive patterns 001 and 012 are 0000, 0100, 0110, 0101, 0111, 0102, and 0103.
Cf.
A328357,
A328358,
A328429,
A328431,
A328432,
A328433,
A328434,
A328435,
A328436,
A328437,
A328438,
A328439,
A328440,
A328441,
A328442.
-
# after Alois P. Heinz in A328357
b := proc(n, x, t) option remember; `if`(n = 0, 1, add(
`if`(t and i <= x, 0, b(n - 1, i, i < x)), i = 0 .. n - 1))
end proc:
a := n -> b(n, -1, false):
seq(a(n), n = 0 .. 24);
-
b[n_, x_, t_] := b[n, x, t] = If[n == 0, 1, Sum[If[t && i <= x, 0, b[n - 1, i, i < x]], {i, 0, n - 1}]];
a[n_] := b[n, -1, False];
a /@ Range[0, 24] (* Jean-François Alcover, Mar 02 2020 after Alois P. Heinz in A328357 *)
A328431
Number of inversion sequences of length n avoiding the consecutive patterns 010, 021, 120, and 210.
Original entry on oeis.org
1, 1, 2, 5, 15, 53, 214, 960, 4701, 24873, 141147, 853641, 5472642, 37024569, 263342224, 1962835806, 15288074104, 124120865849, 1048092680689, 9186689045482, 83435365244510, 783923558286071, 7608398620990535, 76177574145052258, 785853360840424425
Offset: 0
The a(4)=15 length 4 inversion sequences avoiding the consecutive patterns 010, 021, 120, and 210 are 0000, 0110, 0001, 0011, 0111, 0002, 0012, 0112, 0022, 0122, 0003, 0013, 0113, 0023, and 0123.
Cf.
A328357,
A328358,
A328429,
A328430,
A328432,
A328433,
A328434,
A328435,
A328436,
A328437,
A328438,
A328439,
A328440,
A328441,
A328442.
-
# after Alois P. Heinz in A328357
b := proc(n, x, t) option remember; `if`(n = 0, 1, add(
`if`(t and i <> x, 0, b(n - 1, i, x < i)), i = 0 .. n - 1))
end proc:
a := n -> b(n, n, false):
seq(a(n), n = 0 .. 24);
-
b[n_, x_, t_] := b[n, x, t] = If[n == 0, 1, Sum[If[t && i != x, 0, b[n - 1, i, x < i]], {i, 0, n - 1}]];
a[n_] := b[n, n, False];
a /@ Range[0, 24] (* Jean-François Alcover, Mar 02 2020 after Alois P. Heinz in A328357 *)
Showing 1-10 of 15 results.
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