1, 1, 0, 1, 1, 0, 1, 2, 2, 0, 1, 3, 7, 5, 0, 1, 4, 15, 31, 15, 0, 1, 5, 26, 95, 164, 52, 0, 1, 6, 40, 214, 717, 999, 203, 0, 1, 7, 57, 405, 2096, 6221, 6841, 877, 0, 1, 8, 77, 685, 4875, 23578, 60619, 51790, 4140, 0, 1, 9, 100, 1071, 9780, 67354, 297692, 652595, 428131, 21147, 0
Offset: 0
Original entry on oeis.org
1, 3, 12, 59, 339, 2210, 16033, 127643, 1103372, 10269643, 102225363, 1082190554, 12126858113, 143268057587, 1778283994284, 23120054355195, 314017850216371, 4444972514600178, 65435496909148513, 999907522895563403, 15832873029742458796, 259377550023571768075
Offset: 1
From _Joerg Arndt_, Apr 25 2010: (Start)
For n=0 there is one empty string (term a(0)=0 not included here); for n=1 there is one string [0]; for n=2 there are 3 strings [00], [01], and [02];
for n=3 there are a(3)=12 strings (in lexicographic order):
01: [000],
02: [001],
03: [002],
04: [010],
05: [011],
06: [012],
07: [013],
08: [020],
09: [021],
10: [022],
11: [023],
12: [024].
(End)
For a(3) = 12, both the row and loop patterns are AAAAA, AABAA, ABABA, ABBBA, AABCC, ABACA, ABBBC, ABCAB, ABCBA, ABCBD, ABCDA, and ABCDE. - _Robert A. Russell_, Apr 24 2018
- D. E. Knuth, The Art of Computer Programming, vol. 4A, Combinatorial Algorithms, Section 7.2.1.5 (p. 765). - Robert A. Russell, Apr 28 2018
- Alois P. Heinz, Table of n, a(n) for n = 1..514
- Joerg Arndt, Matters Computational (The Fxtbook), section 17.3.4, pp. 364-366.
- Zhanar Berikkyzy, Pamela E. Harris, Anna Pun, Catherine Yan, and Chenchen Zhao, Combinatorial Identities for Vacillating Tableaux, arXiv:2308.14183 [math.CO], 2023. See pp. 18, 29.
- J. Quaintance, Letter representations of rectangular m x n x p proper arrays, arXiv:math/0412244 [math.CO], 2004-2006.
-
b:= proc(n, m) option remember; `if`(n=0, 1,
add(b(n-1, max(m, j)), j=1..m+2))
end:
a:= n-> b(n, -1):
seq(a(n), n=1..25); # Alois P. Heinz, Jun 15 2018
-
Table[Sum[ Binomial[n, k] A002872[[k + 1]], {k, 0, n}], {n, 0, 24}]
Aodd[m_, k_] := Aodd[m, k] = If[m > 1, k Aodd[m-1, k] + Aodd[m-1, k-1]
+ Aodd[m-1, k-2], Boole[m==1 && k==1]]
Table[Sum[Aodd[m, k], {k, 1, 2m-1}], {m, 1, 30}] (* Robert A. Russell, Apr 24 2018 *)
x[n_] := x[n] = If[n<2, n+1, 2x[n-1] + (n-1) x[n-2]]; (* A005425 *)
Table[Sum[StirlingS2[n, k] x[k-1], {k, 0, n}], {n, 30}] (* Robert A. Russell, Apr 28 2018, after Knuth reference *)
-
x='x+O('x^66);
egf=exp(x+exp(x)+exp(2*x)/2-3/2); /* = 1 +3*x +6*x^2 +59/6*x^3 +113/8*x^4 +... */
Vec(serlaplace(egf)) /* Joerg Arndt, Apr 29 2011 */
A189845
Number of length-n restricted growth strings (RGS) [s(0),s(1),...,s(n-1)] where s(0)=0 and s(k)<=3+max(prefix) for k>=1.
Original entry on oeis.org
1, 1, 4, 22, 150, 1200, 10922, 110844, 1236326, 14990380, 195895202, 2740062260, 40789039078, 643118787708, 10696195808162, 186993601880756, 3425688601198118, 65586903427253532, 1309155642001921026, 27185548811026532692, 586164185027289760806
Offset: 0
For n=0 there is one empty string; for n=1 there is one string [0]; for n=2 there are 4 strings [00], [01], [02], and [03];
for n=3 there are a(3)=22 strings:
01: [ 0 0 0 ],
02: [ 0 0 1 ],
03: [ 0 0 2 ],
04: [ 0 0 3 ],
05: [ 0 1 0 ],
06: [ 0 1 1 ],
07: [ 0 1 2 ],
08: [ 0 1 3 ],
09: [ 0 1 4 ],
10: [ 0 2 0 ],
11: [ 0 2 1 ],
12: [ 0 2 2 ],
13: [ 0 2 3 ],
14: [ 0 2 4 ],
15: [ 0 2 5 ],
16: [ 0 3 0 ],
17: [ 0 3 1 ],
18: [ 0 3 2 ],
19: [ 0 3 3 ],
20: [ 0 3 4 ],
21: [ 0 3 5 ],
22: [ 0 3 6 ].
-
b:= proc(n, m) option remember; `if`(n=0, 1,
add(b(n-1, max(m, j)), j=1..m+3))
end:
a:= n-> b(n, -2):
seq(a(n), n=0..25); # Alois P. Heinz, Jun 15 2018
-
b[n_, m_] := b[n, m] = If[n==0, 1, Sum[b[n-1, Max[m, j]], {j, 1, m+3}]];
a[n_] := b[n, -2];
a /@ Range[0, 25] (* Jean-François Alcover, Nov 03 2020, after Alois P. Heinz *)
-
x='x+O('x^66);
egf=exp(x+sum(j=1,3, (exp(j*x)-1)/j)); /* (off by one!) */
concat([1], Vec(serlaplace(egf)))
A305963
Number of length-n restricted growth strings (RGS) with growth <= n and fixed first element.
Original entry on oeis.org
1, 1, 3, 22, 305, 6756, 216552, 9416240, 530764089, 37498693555, 3235722405487, 334075729235172, 40587204883652869, 5722676826879812177, 925590727478445526747, 170032646641380554970304, 35173161711207720944899921, 8132124409499796317194563900
Offset: 0
a(2) = 3: 11, 12, 13.
a(3) = 22: 111, 112, 113, 114, 121, 122, 123, 124, 125, 131, 132, 133, 134, 135, 136, 141, 142, 143, 144, 145, 146, 147.
-
b:= proc(n, k, m) option remember; `if`(n=0, 1,
add(b(n-1, k, max(m, j)), j=1..m+k))
end:
a:= n-> b(n$2, 1-n):
seq(a(n), n=0..20);
# second Maple program:
a:= n-> `if`(n=0, 1, (n-1)!*coeff(series(exp(x+add(
(exp(j*x)-1)/j, j=1..n)), x, n), x, n-1)):
seq(a(n), n=0..20);
-
b[n_, k_, m_] := b[n, k, m] = If[n == 0, 1,
Sum[b[n - 1, k, Max[m, j]], {j, 1, m + k}]];
a[n_] := b[n, n, 1 - n];
Table[a[n], {n, 0, 20}] (* Jean-François Alcover, Mar 21 2022, after Alois P. Heinz *)
A305964
Number of length-n restricted growth strings (RGS) with growth <= four and fixed first element.
Original entry on oeis.org
1, 1, 5, 35, 305, 3125, 36479, 475295, 6811205, 106170245, 1784531879, 32117927231, 615413731205, 12493421510405, 267608512061159, 6026688403933967, 142256385130774229, 3509899012049396645, 90301862963332188839, 2417349828110572405823, 67201548131159391828677
Offset: 0
-
b:= proc(n, m) option remember; `if`(n=0, 1,
add(b(n-1, max(m, j)), j=1..m+4))
end:
a:= n-> b(n, -3):
seq(a(n), n=0..25);
# second Maple program:
a:= n-> `if`(n=0, 1, (n-1)!*coeff(series(exp(x+add(
(exp(j*x)-1)/j, j=1..4)), x, n), x, n-1)):
seq(a(n), n=0..25);
A305965
Number of length-n restricted growth strings (RGS) with growth <= five and fixed first element.
Original entry on oeis.org
1, 1, 6, 51, 541, 6756, 96205, 1530025, 26775550, 509861195, 10472109149, 230368347780, 5396308081285, 133949699318945, 3508794554854054, 96648143868171171, 2790590111082279405, 84231759174460743700, 2651416546964399982909, 86848041397350751409257
Offset: 0
-
b:= proc(n, m) option remember; `if`(n=0, 1,
add(b(n-1, max(m, j)), j=1..m+5))
end:
a:= n-> b(n, -4):
seq(a(n), n=0..25);
# second Maple program:
a:= n-> `if`(n=0, 1, (n-1)!*coeff(series(exp(x+add(
(exp(j*x)-1)/j, j=1..5)), x, n), x, n-1)):
seq(a(n), n=0..25);
A305966
Number of length-n restricted growth strings (RGS) with growth <= six and fixed first element.
Original entry on oeis.org
1, 1, 7, 70, 875, 12887, 216552, 4065775, 84022595, 1889844292, 45857269017, 1191971998455, 32996489835190, 968034453578997, 29972909437783507, 975944207096597110, 33313664777283768535, 1188852507118147925627, 44246989258071738375272, 1713739685432232160181115
Offset: 0
-
b:= proc(n, m) option remember; `if`(n=0, 1,
add(b(n-1, max(m, j)), j=1..m+6))
end:
a:= n-> b(n, -5):
seq(a(n), n=0..25);
# second Maple program:
a:= n-> `if`(n=0, 1, (n-1)!*coeff(series(exp(x+add(
(exp(j*x)-1)/j, j=1..6)), x, n), x, n-1)):
seq(a(n), n=0..25);
A305967
Number of length-n restricted growth strings (RGS) with growth <= seven and fixed first element.
Original entry on oeis.org
1, 1, 8, 92, 1324, 22464, 435044, 9416240, 224382116, 5820361008, 162900823428, 4884515258224, 155992931417316, 5280138035455024, 188639017788288836, 7087660960768335472, 279189959071013966500, 11498108706476961892400, 493881446025566760548100
Offset: 0
-
b:= proc(n, m) option remember; `if`(n=0, 1,
add(b(n-1, max(m, j)), j=1..m+7))
end:
a:= n-> b(n, -6):
seq(a(n), n=0..25);
# second Maple program:
a:= n-> `if`(n=0, 1, (n-1)!*coeff(series(exp(x+add(
(exp(j*x)-1)/j, j=1..7)), x, n), x, n-1)):
seq(a(n), n=0..25);
A305968
Number of length-n restricted growth strings (RGS) with growth <= eight and fixed first element.
Original entry on oeis.org
1, 1, 9, 117, 1905, 36585, 802221, 19664325, 530764089, 15596609985, 494555435781, 16802009359677, 608027982857169, 23322183958778553, 944242763282027421, 40207158379868421429, 1795007963258388557673, 83786699444454149125041, 4079132811705470375924277
Offset: 0
-
b:= proc(n, m) option remember; `if`(n=0, 1,
add(b(n-1, max(m, j)), j=1..m+8))
end:
a:= n-> b(n, -7):
seq(a(n), n=0..25);
# second Maple program:
a:= n-> `if`(n=0, 1, (n-1)!*coeff(series(exp(x+add(
(exp(j*x)-1)/j, j=1..8)), x, n), x, n-1)):
seq(a(n), n=0..25);
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