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A111596 Associated Sheffer triangle to Sheffer triangle A111595. 37
1, 0, 1, 0, -2, 1, 0, 6, -6, 1, 0, -24, 36, -12, 1, 0, 120, -240, 120, -20, 1, 0, -720, 1800, -1200, 300, -30, 1, 0, 5040, -15120, 12600, -4200, 630, -42, 1, 0, -40320, 141120, -141120, 58800, -11760, 1176, -56, 1, 0, 362880, -1451520, 1693440, -846720, 211680, -28224, 2016, -72, 1, 0, -3628800 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

0,5

COMMENTS

Coefficients of Laguerre polynomials (-1)^n * n! * L(n,-1,x), which equals (-1)^n * Lag(n,x,-1) below. Lag(n,Lag(.,x,-1),-1) = x^n evaluated umbrally, i.e., with (Lag(.,x,-1))^k = Lag(k,x,-1). - Tom Copeland, Apr 26 2014

Without row n=0 and column m=0 this is, up to signs, the Lah triangle A008297.

The unsigned column sequences are (with leading zeros): A000142, A001286, A001754, A001755, A001777, A001778, A111597-A111600 for m=1..10.

The row polynomials p(n,x) := Sum_{m=0..n} a(n,m)*x^m, together with the row polynomials s(n,x) of A111595 satisfy the exponential (or binomial) convolution identity s(n,x+y) = Sum_{k=0..n} binomial(n,k)*s(k,x)*p(n-k,y), n>=0.

Exponential Riordan array [1,x/(1+x)]. Inverse of the exponential Riordan array [1,x/(1-x)], which is the unsigned version of A111596. - Paul Barry, Apr 12 2007

For the unsigned subtriangle without column number m=0 and row number n=0, see A105278.

Unsigned triangle also matrix product |S1|*S2 of Stirling number matrices.

The unsigned row polynomials are Lag(n,-x,-1), the associated Laguerre polynomials of order -1 with negated argument. See Gradshteyn and Ryzhik, Abramowitz and Stegun and Rota (Finite Operator Calculus) for extensive formulae. - Tom Copeland, Nov 17 2007, Sep 09 2008

An infinitesimal matrix generator for unsigned A111596 is given by A132792. - Tom Copeland, Nov 22 2007

From the formalism of A132792 and A133314 for n > k, unsigned A111596(n,k) = a(k) * a(k+1)...a(n-1) / (n-k)! = a generalized factorial, where a(n) = A002378(n) = n-th term of first subdiagonal of unsigned A111596. Hence Deutsch's remark in A002378 provides an interpretation of A111596(n,k) in terms of combinations of certain circular binary words. - Tom Copeland, Nov 22 2007

Given T(n,k)= A111596(n,k) and matrices A and B with A(n,k) = T(n,k)*a(n-k) and B(n,k) = T(n,k)*b(n-k), then A*B = C where C(n,k) = T(n,k)*[a(.)+b(.)]^(n-k), umbrally. - Tom Copeland, Aug 27 2008

LINKS

Table of n, a(n) for n=0..56.

Wolfdieter Lang, The first 11 rows of the triangle.

M. Abramowitz and I. A. Stegun, eds., Handbook of Mathematical Functions, National Bureau of Standards, Applied Math. Series 55, Tenth Printing, 1972 [alternative scanned copy].

Paul Barry, Combinatorial polynomials as moments, Hankel transforms and exponential Riordan arrays, arXiv preprint arXiv:1105.3044 [math.CO], 2011.

Tom Copeland, A Class of Differential Operators and the Stirling Numbers, Generators, Inversion, and Matrix, Binomial, and Integral Transforms, Lagrange a la Lah

J. Tayor, Counting words with Laguerre polynomials, DMTCS Proc., Vol. AS, 2013, p. 1131-1142. - From Tom Copeland, Jan 08 2016

FORMULA

E.g.f. m-th column: ((x/(1+x))^m)/m!, m>=0.

E.g.f. for row polynomials p(n, x) is exp(x*y/(1+y)).

a(n, m) = ((-1)^(n-m))*|A008297(n, m)| = ((-1)^(n-m))*(n!/m!)*binomial(n-1, m-1), n>=m>=1; a(0, 0)=1; else 0.

a(n, m) = -(n-1+m)*a(n-1, m) + a(n-1, m-1), n>=m>=0, a(n, -1):=0, a(0, 0)=1; a(n, m)=0 if n<m.

|a(n,m)| = Sum_{k=m..n} |S1(n,k)|*S2(k,m), n>=0. S2(n,m):=A048993. S1(n,m):=A048994. - Wolfdieter Lang, May 04 2007

From Tom Copeland, Nov 21 2011: (Start)

For this Lah triangle, the n-th row polynomial is given umbrally by

  (-1)^n n! binomial(-Bell.(-x),n), where Bell_n(-x)= exp(x)(xd/dx)^n exp(-x), the n-th Bell / Touchard / exponential polynomial with neg. arg., (cf. A008277). E.g., 2! binomial(-Bell.(-x),2) = -Bell.(-x)*(-Bell.(-x)-1) = Bell_2(-x)+Bell_1(-x) = -2x+x^2.

A Dobinski relation is (-1)^n n! binomial(-Bell.(-x),n)= (-1)^n n! e^x Sum_{j>=0} (-1)^j binomial(-j,n)x^j/j!= n! e^x Sum_{j>=0} (-1)^j binomial(j-1+n,n)x^j/j!. See the Copeland link for the relation to inverse Mellin transform. (End)

The n-th row polynomial is (-1/x)^n e^x (x^2*D_x)^n e^(-x). - Tom Copeland, Oct 29 2012

Let f(.,x)^n = f(n,x) = x!/(x-n)!, the falling factorial,and r(.,x)^n = r(n,x) = (x-1+n)!/(x-1)!, the rising factorial, then the Lah polynomials, Lah(n,t)= n!*Sum{k=1..n} binomial(n-1,k-1)(-t)^k/k! (extra sign factor on odd rows), give the transform Lah(n,-f(.,x))= r(n,x), and Lah(n,r(.,x))= (-1)^n * f(n,x). - Tom Copeland, Oct 04 2014

|T(n,k)| = Sum_{j=0..2*(n-k)} A254881(n-k,j)*k^j/(n-k)!. Note that A254883 is constructed analogously from A254882. - Peter Luschny, Feb 10 2015

The T(n,k) are the inverse Bell transform of [1!,2!,3!,...] and |T(n,k)| are the Bell transform of [1!,2!,3!,...]. See A264428 for the definition of the Bell transform and A264429 for the definition of the inverse Bell transform. - Peter Luschny, Dec 20 2015

EXAMPLE

Binomial convolution of row polynomials: p(3,x) = 6*x-6*x^2+x^3; p(2,x) = -2*x+x^2, p(1,x) = x, p(0,x) = 1,

together with those from A111595: s(3,x) = 9*x-6*x^2+x^3; s(2,x) = 1-2*x+x^2, s(1,x) = x, s(0,x) = 1; therefore

9*(x+y)-6*(x+y)^2+(x+y)^3 = s(3,x+y) = 1*s(0,x)*p(3,y) + 3*s(1,x)*p(2,y) + 3*s(2,x)*p(1,y) +1*s(3,x)*p(0,y) = (6*y-6*y^2+y^3) + 3*x*(-2*y+y^2) + 3*(1-2*x+x^2)*y + 9*x-6*x^2+x^3.

From Wolfdieter Lang, Apr 28 2014: (Start)

The triangle a(n,m) begins:

n\m  0     1       2       3      4     5   6  7

0:   1

1:   0     1

2:   0    -2       1

3:   0     6      -6       1

4:   0   -24      36     -12      1

5:   0   120    -240     120    -20     1

6:   0  -720    1800   -1200    300   -30   1

7:   0  5040  -15120   12600  -4200   630 -42  1

...

For more rows see the link.

(End)

MAPLE

# The function BellMatrix is defined in A264428.

BellMatrix(n -> `if`(n::odd, -(n+1)!, (n+1)!), 9); # Peter Luschny, Jan 27 2016

MATHEMATICA

a[0, 0] = 1; a[n_, m_] := ((-1)^(n-m))*(n!/m!)*Binomial[n-1, m-1]; Table[a[n, m], {n, 0, 10}, {m, 0, n}] // Flatten (* Jean-Fran├žois Alcover, Jul 05 2013 *)

T[ n_, k_] := (-1)^n n! Coefficient[ LaguerreL[ n, -1, x], x, k]; (* Michael Somos, Dec 15 2014 *)

PROG

(Sage)

lah_number = lambda n, k: factorial(n-k)*binomial(n, n-k)*binomial(n-1, n-k)

A111596_row = lambda n: [(-1)^(n-k)*lah_number(n, k) for k in (0..n)]

for n in range(10): print A111596_row(n) # Peter Luschny, Oct 05 2014

(Sage)

# The function inverse_bell_transform is defined in A264429.

def A111596_matrix(dim):

    fact = [factorial(n) for n in (1..dim)]

    return inverse_bell_transform(dim, fact)

A111596_matrix(10) # Peter Luschny, Dec 20 2015

(PARI) {T(n, k) = if( n<1 || k<1, n==0 && k==0, (-1)^n * n! * polcoeff( sum(k=1, n, binomial( n-1, k-1) * (-x)^k / k!), k))}; /* Michael Somos, Dec 15 2014 */

CROSSREFS

Row sums: A111884. Unsigned row sums: A000262.

A002868 gives maximal element (in magnitude) in each row.

Cf. A130561 for a natural refinement.

Cf. A264428, A264429.

Sequence in context: A247686 A111184 A271703 * A129062 A163936 A187555

Adjacent sequences:  A111593 A111594 A111595 * A111597 A111598 A111599

KEYWORD

sign,easy,tabl

AUTHOR

Wolfdieter Lang, Aug 23 2005

EXTENSIONS

Name changed and link with first rows erased by Wolfdieter Lang, Apr 28 2014

STATUS

approved

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Last modified May 24 07:35 EDT 2016. Contains 273236 sequences.