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A090210 Triangle of certain generalized Bell numbers. 10
1, 1, 1, 2, 1, 1, 5, 7, 1, 1, 15, 87, 34, 1, 1, 52, 1657, 2971, 209, 1, 1, 203, 43833, 513559, 163121, 1546, 1, 1, 877, 1515903, 149670844, 326922081, 12962661, 13327, 1, 1, 4140, 65766991, 66653198353, 1346634725665, 363303011071, 1395857215, 130922 (list; table; graph; refs; listen; history; internal format)
OFFSET

0,4

COMMENTS

Let B_{n}(x) = sum_{j>=0}(exp(j!/(j-n)!*x-1)/j!) and

S(n,k) = k! [x^k] taylor(B_{n}(x)), where [x^k] denotes the

coefficient of x^k in the Taylor series for B_{n}(x).

Then S(n,k) (n>0, k>=0) is the square array representation of the triangle.

To illustrate the cross-references of T(n,k) when written as a square array.

n\k         A000012,A000012,A002720,A069948,A182925,A182924,...

0: A000012: 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, ...

1: A000110: 1, 1, 2, 5, 15, 52, 203, 877, 4140, ...

2: A020556: 1, 1, 7, 87, 1657, 43833, 1515903, ...

3: A069223: 1, 1, 34, 2971, 513559, 149670844, ...

4: A071379: 1, 1, 209, 163121, 326922081, ...

5: A090209: 1, 1, 1546, 12962661, 363303011071,...

6:  ...     1, 1, 13327, 1395857215, 637056434385865,...

Note that the sequence T(0,k) is not included in the data.

- Peter Luschny, Mar 27 2011

REFERENCES

P. Blasiak, K. A. Penson and A. I. Solomon, The general boson normal ordering problem, Phys. Lett. A 309 (2003) 198-205.

M. Schork, On the combinatorics of normal ordering bosonic operators and deforming it, J. Phys. A 36 (2003) 4651-4665.

LINKS

P. Blasiak, K. A. Penson and A. I. Solomon, The general boson normal ordering problem.

W. Lang, First 8 rows.

K. A. Penson, P. Blasiak, A. Horzela, A. I. Solomon and G. H. E. Duchamp,Laguerre-type derivatives: Dobinski relations and combinatorial identities, J. Math. Phys. 50, 083512 (2009).

FORMULA

a(n, m)= Bell(m;n-(m-1)), n>= m-1 >=0, with Bell(m;k) := sum(S2(m;k, p), p=m..m*k), where S2(m;k, p) := (((-1)^p)/p!)*sum(((-1)^r)*binomial(p, r)*fallfac(p, r)^k, r=m..p); with fallfac(n, m) := A008279(n, m) (falling factorials) and m<=p<=k*m, k>=1, m=1, 2, ..., else 0. From eqs.(6) with r=s->m and eq.(19) with S_{r, r}(n, k)-> S2(r;n, k) of the Blasiak et al. reference.

a(n, m)= (sum(fallfac(k, m)^(n-(m-1)), k=m..infinity))/exp(1), n>= m-1 >=0, else 0. From eq.(26) with r->m of the Schork reference which is rewritten eq.(11) of the original Blasiak et al. reference.

E.g.f. m-th column (no leading zeros): (sum((exp(fallfac(k, m)*x))/k!, k=m..infinity) + A000522(m)/m!)/exp(1). Rewritten from the top of p. 4656 of the Schork reference.

EXAMPLE

Triangle begins:

1;

1, 1;

2, 1, 1;

5, 7, 1, 1;

15, 87, 34, 1, 1;

52, 1657, 2971, 209, 1, 1;

203, 43833, 513559, 163121, 1546, 1, 1;

MAPLE

A090210_AsSquareArray := proc(n, k) local r, s, i;

if k=0 then 1 else r := [seq(n+1, i=1..k-1)]; s := [seq(1, i=1..k-1)];

exp(-x)*n!^(k-1)*hypergeom(r, s, x); round(evalf(subs(x=1, %), 99)) fi end:

seq(lprint(seq(A090210_AsSquareArray(n, k), k=0..6)), n=0..6);

- Peter Luschny, Mar 30 2011

MATHEMATICA

t[n_, k_] := t[n, k] = Sum[(n+j)!^(k-1)/(j!^k*E), {j, 0, Infinity}]; t[_, 0] = 1;

Flatten[ Table[ t[n-k+1, k], {n, 0, 8}, {k, n, 0, -1}]][[1 ;; 43]] (* From Jean-François Alcover, Jun 17 2011 *)

CROSSREFS

Cf. A000110, A020556, A069223, A071379, A090209, A002720, A069948, A182924, A182925, A182933.

Sequence in context: A064814 A051012 A064644 * A168131 A024462 A049252

Adjacent sequences:  A090207 A090208 A090209 * A090211 A090212 A090213

KEYWORD

nonn,easy,tabl

AUTHOR

Wolfdieter Lang (wolfdieter.lang_AT_physik_DOT_uni-karlsruhe_DOT_de), Dec 01 2003

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Last modified February 18 00:14 EST 2012. Contains 206085 sequences.