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A073107 Triangle T(n,k) read by rows, where e.g.f. for T(n,k) is exp((1+y)*x)/(1-x) (with n >= 0 and 0 <= k <= n). 5
1, 2, 1, 5, 4, 1, 16, 15, 6, 1, 65, 64, 30, 8, 1, 326, 325, 160, 50, 10, 1, 1957, 1956, 975, 320, 75, 12, 1, 13700, 13699, 6846, 2275, 560, 105, 14, 1, 109601, 109600, 54796, 18256, 4550, 896, 140, 16, 1, 986410, 986409, 493200, 164388, 41076, 8190, 1344 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

Triangle is second binomial transform of A008290. - Paul Barry, May 25 2006

-exp(-x)*Sum(k=0,n,T[n,k]*x^k) = Integral (x+1)^n*exp(-x) dx = -exp(1)*Gamma(n+1,x+1). - Gerald McGarvey, Mar 15 2009

Ignoring signs, n-th row is the coefficient list of the permanental polynomial of the n X n matrix with 2's along the main diagonal and 1's everywhere else (see Mathematica code below). - John M. Campbell, Jul 02 2012

LINKS

Table of n, a(n) for n=0..51.

Wikipedia, Sheffer sequence.

FORMULA

O.g.f. for k-th column is 1/k!*Sum_{i >= k} i!*x^i/(1-x)^(i+1). For n > 0, T(n, 0) = floor(n!*exp(1)) = A000522(n), T(n, 1) = floor(n!*exp(1) - 1) = A007526(n), T(n, 2) = 1/2!*floor(n!*exp(1) - 1 - n) = A038155(n), T(n, 3) = 1/3!*floor(n!*exp(1) - 1 - n - n*(n - 1)), T(n, 4) = 1/4!*floor(n!*exp(1) - 1 - n - n*(n - 1) - n*(n - 1)*(n - 2)), ... . Row sums give A010842.

E.g.f. for k-th column is x^k/k!*exp(x)/(1 - x).

O.g.f. for k-th row is n!*Sum_{k = 0..n} (1 + x)^k/k!.

T(n,k) = Sum_{j = 0..n} binomial(j,k)*n!/j!. - Paul Barry, May 25 2006

From Peter Bala, Sep 20 2012: (Start)

Exponential Riordan array [exp(x)/(1-x),x] belonging to the Appell subgroup, which factorizes in the Appell group as [1/1-x,x]*[exp(x),x] = A094587*A007318.

The n-th row polynomial R(n,x) of the triangle satisfies d/dx(R(n,x)) = n*R(n-1,x), as well as R(n,x + y) = Sum {k = 0..n} binomial(n,k)*R(k,x)*y^(n-k). The row polynomials are a Sheffer sequence of Appell type.

Matrix inverse of triangle is a signed version of A093375.

(End)

From Tom Copeland, Oct 20 2015: (Start)

The raising operator, with D = d/dx, for the row polynomials is RP = x + d{log[e^D/(1-D)]}/dD = x + 1 + 1/(1-D) =  x + 2 + D + D^2 + ..., i.e., RP R(n,x) = R(n+1,x).

This operator is the limit as t tends to 1 of the raising operator of the polynomials p(n,x;t) described in A046802, implying R(n,x) = p(n,x;1). Compare with the raising operator of A094587, x + 1/(1-D), and that of signed A093375, x - 1 - 1/(1-D).

From the Appell formalism, the row polynomials RI(n,x) of signed A093375 are the umbral inverse of this entry's row polynomials; that is, R(n,RI(.,x)) = x^n = RI(n,R(.,x)) under umbral composition.

(End)

EXAMPLE

exp((1 + y)*x)/(1 - x) =

  1 +

  1/! * (2 + y) * x +

  1/2! * (5 + 4*y + y^2) * x^2 +

  1/3! * (16 + 15*y + 6*y^2 + y^3) * x^3 +

  1/4! * (65 + 64*y + 30*y^2 + 8*y^3 + y^4) * x^4 +

  1/5! * (326 + 325*y + 160*y^2 + 50*y^3 + 10*y^4 + y^5) * x^5 + ...

MATHEMATICA

Permanent[m_List] := With[{v=Array[x, Length[m]]}, Coefficient[Times@@(m.v), Times@@v]] ;

A[q_] := Array[KroneckerDelta[#1, #2] + 1&, {q, q}] ;

n = 1 ; While[n < 10, Print[Abs[CoefficientList[Permanent[A[n] - IdentityMatrix[n] * k], k]]]; n++] (* John M. Campbell, Jul 02 2012 *)

CROSSREFS

Cf. A008290, A008291, A046802, A093375 (unsigned inverse), A094587.

Column 0 is A000522.

Sequence in context: A137650 A171515 A110271 * A248669 A103718 A113350

Adjacent sequences:  A073104 A073105 A073106 * A073108 A073109 A073110

KEYWORD

easy,nonn,tabl

AUTHOR

Vladeta Jovovic, Aug 19 2002

EXTENSIONS

More terms from Emeric Deutsch, Feb 23 2004

STATUS

approved

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Last modified February 22 12:00 EST 2020. Contains 332135 sequences. (Running on oeis4.)