A004747 Triangle read by rows: the Bell transform of the triple factorial numbers A008544 without column 0.
1, 2, 1, 10, 6, 1, 80, 52, 12, 1, 880, 600, 160, 20, 1, 12320, 8680, 2520, 380, 30, 1, 209440, 151200, 46480, 7840, 770, 42, 1, 4188800, 3082240, 987840, 179760, 20160, 1400, 56, 1, 96342400, 71998080, 23826880, 4583040, 562800, 45360, 2352, 72, 1
Offset: 1
Examples
Triangle begins: 1; 2, 1; 10, 6, 1; 80, 52, 12, 1; 880, 600, 160, 20, 1; 12320, 8680, 2520, 380, 30, 1; 209440, 151200, 46480, 7840, 770, 42, 1; Tree combinatorics for T(3,2)=6: Consider first the unordered forest of m=2 plane trees with n=3 vertices, namely one vertex with out-degree r=0 (root) and two different trees with two vertices (one root with out-degree r=1 and a leaf with r=0). The 6 increasing labelings come then from the forest with rooted (x) trees x, o-x (1,(3,2)), (2,(3,1)) and (3,(2,1)) and similarly from the second forest x, x-o (1,(2,3)), (2,(1,3)) and (3,(1,2)).
Links
- G. C. Greubel, Rows n = 1..50 of the triangle, flattened
- F. Bergeron, Ph. Flajolet and B. Salvy, Varieties of increasing trees, Lecture Notes in Computer Science vol. 581, ed. J.-C. Raoult, Springer 1992, pp. 24-48.
- P. Blasiak, K. A. Penson and A. I. Solomon, The general boson normal ordering problem, arXiv:quant-ph/0402027, 2004.
- Richell O. Celeste, Roberto B. Corcino, and Ken Joffaniel M. Gonzales. Two Approaches to Normal Order Coefficients, Journal of Integer Sequences, Vol. 20 (2017), Article 17.3.5.
- Tom Copeland, A Class of Differential Operators and the Stirling Numbers
- Milan Janjic, Some classes of numbers and derivatives, JIS 12 (2009) #09.8.3.
- Wolfdieter Lang, On generalizations of Stirling number triangles, J. Integer Seqs., Vol. 3 (2000), #00.2.4.
- Wolfdieter Lang, Combinatorial Interpretation of Generalized Stirling Numbers, J. Int. Seqs. Vol. 12 (2009) #09.3.3.
- Mathias Pétréolle and Alan D. Sokal, Lattice paths and branched continued fractions. II. Multivariate Lah polynomials and Lah symmetric functions, arXiv:1907.02645 [math.CO], 2019.
- Index entries for sequences related to Bessel functions or polynomials
Crossrefs
Programs
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Magma
function T(n,k) // T = A004747 if k eq 0 then return 0; elif k eq n then return 1; else return (3*(n-1)-k)*T(n-1,k) + T(n-1,k-1); end if; end function; [T(n,k): k in [1..n], n in [1..12]]; // G. C. Greubel, Oct 03 2023
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Maple
T := (n, m) -> 3^n/m!*(1/3*m*GAMMA(n-1/3)*hypergeom([1-1/3*m, 2/3-1/3*m, 1/3-1/3*m], [2/3, 4/3-n], 1)/GAMMA(2/3)-1/6*m*(m-1)*GAMMA(n-2/3)*hypergeom( [1-1/3*m, 2/3-1/3*m, 4/3-1/3*m], [4/3, 5/3-n], 1)/Pi*3^(1/2)*GAMMA(2/3)): for n from 1 to 6 do seq(simplify(T(n,k)),k=1..n) od; # Karol A. Penson, Feb 06 2004 # The function BellMatrix is defined in A264428. # Adds (1,0,0,0, ..) as column 0. BellMatrix(n -> mul(3*k+2, k=(0..n-1)), 9); # Peter Luschny, Jan 29 2016
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Mathematica
(* First program *) T[1,1]= 1; T[, 0]= 0; T[0, ]= 0; T[n_, m_]:= (3*(n-1)-m)*T[n-1, m]+T[n-1, m-1]; Flatten[Table[T[n, m], {n,12}, {m,n}] ][[1 ;; 45]] (* Jean-François Alcover, Jun 16 2011, after recurrence *) (* Second program *) f[n_, m_]:= m/n Sum[Binomial[k, n-m-k] 3^k (-1)^(n-m-k) Binomial[n+k-1, n-1], {k, 0, n-m}]; Table[n! f[n, m]/(m! 3^(n-m)), {n,12}, {m,n}]//Flatten (* Michael De Vlieger, Dec 23 2015 *) (* Third program *) rows = 12; T[n_, m_]:= BellY[n, m, Table[Product[3k+2, {k, 0, j-1}], {j, 0, rows}]]; Table[T[n, m], {n,rows}, {m,n}]//Flatten (* Jean-François Alcover, Jun 22 2018 *)
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Sage
# uses [bell_transform from A264428] triplefactorial = lambda n: prod(3*k+2 for k in (0..n-1)) def A004747_row(n): trifact = [triplefactorial(k) for k in (0..n)] return bell_transform(n, trifact) [A004747_row(n) for n in (0..10)] # Peter Luschny, Dec 21 2015
Formula
T(n, m) = n!*A048966(n, m)/(m!*3^(n-m));
T(n+1, m) = (3*n-m)*T(n, m)+ T(n, m-1), for n >= m >= 1, with T(n, m) = 0, for n
E.g.f. of m-th column: ( 1 - (1-3*x)^(1/3) )^m/m!.
Sum_{k=1..n} T(n, k) = A015735(n).
For a formula expressed as special values of hypergeometric functions 3F2 see the Maple program below. - Karol A. Penson, Feb 06 2004
T(n,1) = A008544(n-1). - Peter Luschny, Dec 23 2015
Extensions
New name from Peter Luschny, Dec 21 2015
A025756 3rd-order Vatalan numbers (generalization of Catalan numbers).
1, 1, 4, 22, 139, 949, 6808, 50548, 384916, 2988418, 23559826, 188061592, 1516680130, 12337999870, 101111413540, 833914857316, 6916004156083, 57638242134229, 482444724374734, 4053815358183454, 34181335453533439
Offset: 0
Keywords
Links
- Vincenzo Librandi, Table of n, a(n) for n = 0..200
- Wolfdieter Lang, On generalizations of Stirling number triangles, J. Integer Seqs., Vol. 3 (2000), #00.2.4.
- T. M. Richardson, The Super Patalan Numbers, arXiv preprint arXiv:1410.5880, 2014 and J. Int. Seq. 18 (2015) # 15.3.3
Crossrefs
Programs
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Maple
A025756 := proc(n) coeftayl( 3/(2+(1-9*x)^(1/3)), x=0, n); end proc: seq(A025756(n), n=0..30); # Wesley Ivan Hurt, Aug 02 2014
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Mathematica
Table[SeriesCoefficient[3/(2+(1-9*x)^(1/3)),{x,0,n}],{n,0,20}] (* Vaclav Kotesovec, Oct 08 2012 *)
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Maxima
a[0]:1$ a[n]:=(1/n)*((9*n-6)*a[n-1]-2*sum(a[k]*a[n-1-k], k, 0, n-1))$ makelist(a[n],n,0,1000); /* Tani Akinari, Aug 02 2014 */
Formula
G.f.: 3 / (2+(1-9*x)^(1/3)).
a(n) = Sum_{m=1..n-1} (m/n) * Sum_{k=1..n-m} binomial(k,n-m-k) * 3^k * (-1)^(n-m-k) * binomial(n+k-1,n-1) + 1. - Vladimir Kruchinin, Feb 08 2011
Conjecture: n*(n-1)*a(n) -(n-1)*(19*n-36)*a(n-1) +9*(11*n^2-51*n+60)*a(n-2) -9*(3*n-7)*(3*n-8)*a(n-3) = 0. - R. J. Mathar, Nov 14 2011
a(n) ~ 9^n/(4*Gamma(2/3)*n^(4/3)). - Vaclav Kotesovec, Oct 08 2012
a(n) = (-1)^(n+1) * 3^(2*n+1) * Sum_{k>=0} (-1/2)^(k+1) * binomial(k/3,n). - Seiichi Manyama, Aug 04 2024
A049213 A convolution triangle of numbers obtained from A025749.
1, 6, 1, 56, 12, 1, 616, 148, 18, 1, 7392, 1904, 276, 24, 1, 93632, 25312, 4080, 440, 30, 1, 1230592, 344960, 59808, 7360, 640, 36, 1, 16612992, 4792128, 876960, 118224, 11960, 876, 42, 1, 228890112, 67586816, 12900416, 1860992, 209200, 18096, 1148
Offset: 1
Comments
Links
- W. Lang, On generalizations of Stirling number triangles, J. Integer Seqs., Vol. 3 (2000), #00.2.4.
Programs
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Mathematica
a[n_, n_] = 1; a[n_, m_] := m/n * 4^(n-m) * Sum[ Binomial[n+k-1, n-1] * Sum[ Binomial[j, n-m-3*k+2*j] * 4^(j-k) * Binomial[k, j] * 3^(-n+m+3*k-j) * 2^(n-m-3*k+j) * (-1)^(n-m-3*k+2*j), {j, 0, k}], {k, 1, n-m}]; Table[a[n, m], {n, 1, 9}, {m, 1, n}] // Flatten (* Jean-François Alcover, Jul 05 2013, after Vladimir Kruchinin *)
Formula
a(n, m) = 4*(4*(n-1)-m)*a(n-1, m)/n + m*a(n-1, m-1)/n, n >= m >= 1; a(n, m) := 0, n < m; a(n, 0) := 0; a(1, 1)=1.
a(n,m) = (m/n) * 4^(n-m) * Sum_{k=1..n-m} binomial(n+k-1, n-1) * Sum_{j=0..k} binomial(j, n-m-3*k+2*j) * 4^(j-k) * binomial(k,j) * 3^(-n+m+3*k-j) * 2^(n-m-3*k+j) * (-1)^(n-m-3*k+2*j), n > m; a(n,n)=1. - Vladimir Kruchinin, Feb 08 2011
A049223 A convolution triangle of numbers obtained from A025750.
1, 10, 1, 150, 20, 1, 2625, 400, 30, 1, 49875, 8250, 750, 40, 1, 997500, 174750, 17875, 1200, 50, 1, 20662500, 3780000, 419625, 32500, 1750, 60, 1, 439078125, 83128125, 9810000, 839500, 53125, 2400, 70, 1, 9513359375, 1852500000, 229359375
Offset: 1
Comments
Links
- W. Lang, On generalizations of Stirling number triangles, J. Integer Seqs., Vol. 3 (2000), #00.2.4.
Programs
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Maxima
T(n,m):=(m*sum((-1)^(n-m-3*k)*binomial(n+k-1,n-1)*sum(2^j*binomial(k,j)*sum(binomial(j,i-j)*binomial(k-j,n-m-3*(k-j)-i)*5^(3*(k-j)+i),i,j,n-m-k+j),j,0,k),k,0,n-m))/n; /* Vladimir Kruchinin, Dec 10 2011 */
Formula
a(n, m) = 5*(5*(n-1)-m)*a(n-1, m)/n + m*a(n-1, m-1)/n, n >= m >= 1; a(n, m) := 0, n
T(n,m) = (m*sum(k=0..n-m, (-1)^(n-m-3*k)*binomial(n+k-1,n-1)*sum(j=0..k, 2^j*binomial(k,j)*sum(i=j..n-m-k+j, binomial(j,i-j)*binomial(k-j,n-m-3*(k-j)-i)*5^(3*(k-j)+i)))))/n. - Vladimir Kruchinin, Dec 10 2011
A049224 A convolution triangle of numbers obtained from A025751.
1, 15, 1, 330, 30, 1, 8415, 885, 45, 1, 232254, 26730, 1665, 60, 1, 6735366, 825858, 58320, 2670, 75, 1, 202060980, 25992252, 2003562, 106560, 3900, 90, 1, 6213375135, 830282805, 68351283, 4038741, 174825, 5355, 105, 1, 194685754230
Offset: 1
Comments
Links
- W. Lang, On generalizations of Stirling number triangles, J. Integer Seqs., Vol. 3 (2000), #00.2.4.
Programs
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Maxima
T(n,m):=(m*sum(binomial(-m+2*i-1,i-1)*2^(2*n-2*i)*sum(binomial(k,n-k-i)*3^(k+i-m)*(-1)^(n-k-i)*binomial(n+k-1,n-1),k,0,n-i),i,m,n))/n; /* Vladimir Kruchinin, Dec 21 2011 */
Formula
a(n, m) = 6*(6*(n-1)-m)*a(n-1, m)/n + m*a(n-1, m-1)/n, n >= m >= 1; a(n, m) := 0, n
G.f.: [(1-(1-36*x)^(1/6))/6]^m=sum(n>=m, T(n,m)*x^n), T(n,m)=(m*sum(i=m..n, binomial(-m+2*i-1,i-1)*2^(2*n-2*i)*sum(k=0..n-i, binomial(k,n-k-i)*3^(k+i-m)*(-1)^(n-k-i)*binomial(n+k-1,n-1))))/n. - Vladimir Kruchinin, Dec 21 2011
Comments