A001515 -id:A001515 - cp's OEIS frontend

A132062 Sheffer triangle (1,1-sqrt(1-2*x)). Extended Bessel triangle A001497.

1, 0, 1, 0, 1, 1, 0, 3, 3, 1, 0, 15, 15, 6, 1, 0, 105, 105, 45, 10, 1, 0, 945, 945, 420, 105, 15, 1, 0, 10395, 10395, 4725, 1260, 210, 21, 1, 0, 135135, 135135, 62370, 17325, 3150, 378, 28, 1, 0, 2027025, 2027025, 945945, 270270, 51975, 6930, 630, 36, 1, 0

Offset: 0

Wolfdieter Lang Sep 14 2007

This is a Jabotinsky type exponential convolution triangle related to A001147 (double factorials). For Jabotinsky type triangles See the D. E. Knuth reference given under A039692.
The subtriangle (n>=m>=1) is A001497(n,m) (Bessel).
For the combinatorial interpretation in terms of unordered forests of increasing plane trees see the W. Lang comment and example under A001497.
This is a special type of Sheffer triangle. See the S. Roman reference given under A048854 (the notation here differs).
This triangle (or the A001497 subtriangle) appears as generalized Stirling numbers of the second kind, S2p(-1,n,m):=S2(-k;m,m)*(-1)^(n-m) for k=1, eqs. (27)-(29) of the W. Lang reference.
Also the Bell transform of the double factorial of odd numbers A001147. For the Bell transform of the double factorial of even numbers A000165 see A039683. For the definition of the Bell transform see A264428. - Peter Luschny, Dec 20 2015

			[1]
[0,      1]
[0,      1,      1]
[0,      3,      3,     1]
[0,     15,     15,     6,     1]
[0,    105,    105,    45,    10,    1]
[0,    945,    945,   420,   105,   15,   1]
[0,  10395,  10395,  4725,  1260,  210,  21,  1]
[0, 135135, 135135, 62370, 17325, 3150, 378, 28, 1]

Toufik Mansour, Matthias Schork and Mark Shattuck, On the Stirling numbers associated with the meromorphic Weyl algebra, Applied Mathematics Letters, Volume 25, Issue 11, November 2012, Pages 1767-1771. - From N. J. A. Sloane, Sep 15 2012
Steven Roman, The Umbral Calculus, Pure and Applied Mathematics, 111, Academic Press, 1984. (p. 78) [Emanuele Munarini, Oct 10 2017]

Leonard Carlitz, A Note on the Bessel Polynomials, Duke Math. J. 24 (2) (1957), 151-162. [_Emanuele Munarini_, Oct 10 2017]
H. Han and S. Seo, Combinatorial proofs of inverse relations and log-concavity for Bessel numbers, Eur. J. Combinat. 29 (7) (2008) 1544-1554. [From _R. J. Mathar_, Mar 20 2009]
Wolfdieter Lang, On generalizations of Stirling number triangles, J. Integer Seqs., Vol. 3 (2000), #00.2.4.
Wolfdieter Lang, First 10 rows.
Robert S. Maier, Boson Operator Ordering Identities from Generalized Stirling and Eulerian Numbers, arXiv:2308.10332 [math.CO], 2023. See p. 18.

Columns m=1: A001147.
Row sums give [1, A001515]. Alternating row sums give [1, -A000806].
Cf. A122850. - R. J. Mathar, Mar 20 2009
Cf. A039683, A264428.

# The function BellMatrix is defined in A264428.
BellMatrix(n -> doublefactorial(2*n-1), 9); # Peter Luschny, Jan 27 2016
# Alternative:
egf := exp(y*(1 - sqrt(1 - 2*x))): serx := series(egf, x, 12):
coefx := n -> n!*coeff(serx, x, n): row := n -> seq(coeff(coefx(n), y, k), k = 0..n): for n from 0 to 8 do row(n) od;  # Peter Luschny, Apr 25 2024

Table[If[k <= n, Binomial[2n-2k,n-k] Binomial[2n-k-1,k-1] (n-k)!/2^(n-k), 0], {n, 0, 6}, {k, 0, n}] // Flatten (* Emanuele Munarini, Oct 10 2017 *)
BellMatrix[f_Function, len_] := With[{t = Array[f, len, 0]}, Table[BellY[n, k, t], {n, 0, len - 1}, {k, 0, len - 1}]];
rows = 10;
M = BellMatrix[(2#-1)!!&, rows];
Table[M[[n, k]], {n, 1, rows}, {k, 1, n}] // Flatten (* Jean-François Alcover, Jun 23 2018, after Peter Luschny *)

# uses[bell_transform from A264428]
def A132062_row(n):
    a = sloane.A001147
    dblfact = a.list(n)
    return bell_transform(n, dblfact)
[A132062_row(n) for n in (0..9)] # Peter Luschny, Dec 20 2015

a(n,m)=0 if n

E.g.f. m-th column ((x*f2p(1;x))^m)/m!, m>=0. with f2p(1;x):=1-sqrt(1-2*x)= x*c(x/2) with the o.g.f.of A000108 (Catalan).

From Emanuele Munarini, Oct 10 2017: (Start)

a(n,k) = binomial(2*n-2*k,n-k)*binomial(2*n-k-1,k-1)*(n-k)!/2^(n-k).

The row polynomials p_n(x) (studied by Carlitz) satisfy the recurrence: p_{n+2}(x) - (2*n+1)*p_{n+1}(x) - x^2*p_n(x) = 0. (End)

T(n, k) = n! [y^k] [x^n] exp(y*(1 - sqrt(1 - 2*x))). - Peter Luschny, Apr 25 2024

A144301 a(0) = a(1) = 1; thereafter a(n) = (2n-3)a(n-1) + a(n-2).

Original entry on oeis.org

1, 1, 2, 7, 37, 266, 2431, 27007, 353522, 5329837, 90960751, 1733584106, 36496226977, 841146804577, 21065166341402, 569600638022431, 16539483668991901, 513293594376771362, 16955228098102446847, 593946277027962411007, 21992967478132711654106, 858319677924203716921141

Offset: 0

David Applegate and N. J. A. Sloane, Dec 07 2008

A variant of A001515, which is the main entry.

a(n) = number of increasing ordered trees on the vertex set [0,n] (counted by the double factorials A001147) in which n is the label on the leaf that terminates the leftmost path from the root. - David Callan, Aug 24 2011

			G.f. = 1 + x + 2*x^2 + 7*x^3 + 37*x^4 + 266*x^5 + 2431*x^6 + 27007*x^7 + ...

G. C. Greubel, Table of n, a(n) for n = 0..400
E. Grosswald, Bessel Polynomials, Lecture Notes Math., Vol. 698, 1978.
Toufik Mansour, Matthias Schork and Mark Shattuck, On the Stirling numbers associated with the meromorphic Weyl algebra, Applied Mathematics Letters, Volume 25, Issue 11, November 2012, Pages 1767-1771. - From _N. J. A. Sloane_, Sep 15 2012
W. Mlotkowski and A. Romanowicz, A family of sequences of binomial type, Probability and Mathematical Statistics, Vol. 33, Fasc. 2 (2013), pp. 401-408.

See A001515 for much more about this sequence.

See A144498 for first differences.

[1] cat [n le 1 select n+1 else (2*n-1)*Self(n) + Self(n-1): n in [0..20]]; // Vincenzo Librandi, Jul 23 2015

a[n_]:= HypergeometricPFQ[{n, 1 - n}, {}, -1/2]; (* Michael Somos, Nov 22 2013 *)
a[n_]:= With[{m= If[n<1, -n, n-1]}, Sum[(m+k)!/((m-k)! k! 2^k), {k,0,m}]]; (* Michael Somos, Nov 22 2013 *)
RecurrenceTable[{a[0]==a[1]==1, a[n]==(2*n-3)*a[n-1] +a[n-2]}, a, {n, 25}] (* Vincenzo Librandi, Jul 23 2015 *)
nxt[{n_,a_,b_}]:={n+1,b,b(2n-1)+a}; NestList[nxt,{1,1,1},30][[All,2]] (* Harvey P. Dale, Nov 29 2022 *)

{a(n) = my(m = if( n<1, -n, n-1)); sum( k=0, m,  (m+k)! / (k! * (m-k)! * 2^k))}; /* Michael Somos, Nov 22 2013 */

def A144301(n): return int(n==0) + sum(binomial(n-1,k)*factorial(n+k-1)/(2^k*factorial(n-1)) for k in range(n))
[A144301(n) for n in range(31)] # G. C. Greubel, Sep 29 2023

a(n) = A001515(n-1) for n>= 1.
E.g.f.: A(x) = exp(1-sqrt(1-2*x)) satisfies A'(x) = A(x)/(1-sqrt(1-2*x)).
Hence a(n+1) = Sum_{k=0..n} ( a(n-k)*binomial(n,k)*(2*k)!/(k!*2^k) ).
A''(x) = (A'(x)/(1-2*x))*(1 + 1/sqrt(1-2*x)).
A''(x) = 2*x*A''(x) + A'(x) + A(x), which is equivalent to the recurrence in the definition.
a(n) = Sum_{k=0..n-1} binomial(n+k-1,2*k)*(2*k)!/(k!*2^k). [See Grosswald, p. 6, Eq. (8).]
a(n) ~ exp(1)*(2n-1)!/(n!*2^n) as n -> oo. [See Grosswald, p. 124]
From Sergei N. Gladkovskii, Oct 06 2012: (Start)
G.f.: 1+x/U(0) where U(k) = 1 - x - x*(2*k+1)/(1 - x - 2*x*(k+1)/U(k+1)); (continued fraction).
G.f.: 1+x*(1-x)/U(0) where U(k) = 1 - 3*x + x^2 - x*4*k - x^2*(2*k+1)*(2*k+2)/U(k+1) ; (continued fraction). (End)
E.g.f.: E(0)/2, where E(k) = 1 + 1/(1 - 2*x/(2*x + (k+1)*(1+sqrt(1-2*x))/E(k+1))); (continued fraction). - Sergei N. Gladkovskii, May 23 2013
G.f.: conjecture: 1 + x*(1-x)/(1-3*x+x^2)*Q(0), where Q(k) = 1 - 2*(k+1)*(2*k+1)*x^2/(2*(k+1)*(2*k+1)*x^2 - (1 - 3*x + x^2 - 4*x*k)*(1 - 7*x + x^2 - 4*x*k)/Q(k+1)); (continued fraction). - Sergei N. Gladkovskii, Nov 19 2013
a(1 - n) = a(n) for all n in Z. (a(n+1) + a(n+2))^2 = a(n)*a(n+2) + a(n+1)*a(n+3) for all integer n. - Michael Somos, Nov 22 2013
G.f.: 1 + x/(1-x)*T(0), where T(k) = 1 - x*(k+1)/( x*(k+1) - (1-x)^2/T(k+1) ); (continued fraction). - Sergei N. Gladkovskii, Nov 26 2013

More terms from Vincenzo Librandi, Jul 23 2015

A144502 Square array read by antidiagonals upwards: T(n,k) is the number of scenarios for the gift exchange problem in which each gift can be stolen at most once, when there are n gifts in the pool and k gifts (not yet frozen) in peoples' hands.

Original entry on oeis.org

1, 1, 1, 2, 2, 1, 7, 7, 5, 1, 37, 37, 30, 16, 1, 266, 266, 229, 155, 65, 1, 2431, 2431, 2165, 1633, 946, 326, 1, 27007, 27007, 24576, 19714, 13219, 6687, 1957, 1, 353522, 353522, 326515, 272501, 198773, 119917, 53822, 13700, 1, 5329837, 5329837, 4976315, 4269271, 3289726, 2199722, 1205857, 486355, 109601, 1

Offset: 0

David Applegate and N. J. A. Sloane, Dec 13 2008

			The array, A(n,k), begins:
    1,    1,     1,      1,       1,        1, ...
    1,    2,     5,     16,      65,      326, ...
    2,    7,    30,    155,     946,     6687, ...
    7,   37,   229,   1633,   13219,   119917, ...
   37,  266,  2165,  19714,  198773,  2199722, ...
  266, 2431, 24576, 272501, 3289726, 42965211, ...
  ...
Antidiagonal triangle, T(n,k), begins as:
      1;
      1,     1;
      2,     2,     1;
      7,     7,     5,     1;
     37,    37,    30,    16,     1;
    266,   266,   229,   155,    65,    1;
   2431,  2431,  2165,  1633,   946,  326,    1;
  27007, 27007, 24576, 19714, 13219, 6687, 1957,   1;

G. C. Greubel, Antidiagonals n = 0..50, flattened
Moa Apagodu, David Applegate, N. J. A. Sloane, and Doron Zeilberger, Analysis of the Gift Exchange Problem, arXiv:1701.08394 [math.CO], 2017.
David Applegate and N. J. A. Sloane, The Gift Exchange Problem, arXiv:0907.0513 [math.CO], 2009.

Rows include A000522, A144495, A144496, A144497.
Columns include A144301, A001515, A144498, A144499, A144500.
Main diagonal is A144501.
Antidiagonal sums give A144503.

A144301:= func< n | (&+[ Binomial(n+k-1,2*k)*Factorial(2*k)/( Factorial(k)*2^k): k in [0..n]]) >;
function A(n,k)
  if n eq 0 then return 1;
  elif k eq 0 then return A144301(n);
  elif k eq 1 then return A144301(n+1);
  else return A(n-1,k+1) + k*A(n,k-1);
  end if;
end function;
A144502:= func< n,k | A(n-k, k) >;
[A144502(n,k): k in [0..n], n in [0..12]]; // G. C. Greubel, Sep 29 2023

B:=proc(p,r) option remember;
if p=0 then RETURN(1); fi;
if r=0 then RETURN(B(p-1,1)); fi;
B(p-1,r+1)+r*B(p,r-1); end;
seq(seq(B(d-k, k), k=0..d), d=0..9);

t[0, ]= 1; t[n, 0]:= t[n, 0]= t[n-1, 1];
t[n_, k_]:= t[n, k]= t[n-1, k+1] + k*t[n, k-1];
Table[t[n-k, k], {n,0,12}, {k,0,n}]//Flatten (* Jean-François Alcover, Jan 14 2014, after Maple *)

def A144301(n): return 1 if n<2 else (2*n-3)*A144301(n-1)+A144301(n-2)
@CachedFunction
def A(n,k):
    if n==0: return 1
    elif k==0: return A144301(n)
    elif k==1: return A144301(n+1)
    else: return A(n-1,k+1) + k*A(n,k-1)
def A144502(n,k): return A(n-k,k)
flatten([[A144502(n,k) for k in range(n+1)] for n in range(13)]) # G. C. Greubel, Sep 29 2023

Let A_n(x) be the e.g.f. for row n. Then A_0(x) = exp(x) and for n >= 1, A_n(x) = (d/dx)A_{n-1}(x)/(1-x).

For n >= 1, the rows A_{n}(x) = P_{n}(x)*exp(x)/(1-x)^(2*n), where P_{n}(x) = (1-x)*(d/dx)( P_{n-1}(x) ) + (2*n-x)*P_{n-1}(x) and P_{0}(x) = 1. - G. C. Greubel, Oct 08 2023

6 more terms from Michel Marcus, Feb 01 2023

A157401 A partition product of Stirling_2 type [parameter k = 1] with biggest-part statistic (triangle read by rows).

Original entry on oeis.org

1, 1, 1, 1, 1, 3, 3, 1, 9, 12, 15, 1, 25, 60, 75, 105, 1, 75, 330, 450, 630, 945, 1, 231, 1680, 3675, 4410, 6615, 10395, 1, 763, 9408, 30975, 41160, 52920, 83160, 135135, 1, 2619, 56952, 233415, 489510, 555660, 748440, 1216215

Offset: 1

Peter Luschny, Mar 09 2009, Mar 14 2009

Partition product of prod_{j=0..n-1}((k + 1)*j - 1) and n! at k = 1,
summed over parts with equal biggest part (see the Luschny link).
Underlying partition triangle is A143171.
Same partition product with length statistic is A001497.
Diagonal a(A000217) = A001147.
Row sum is A001515.

Peter Luschny, Counting with Partitions.
Peter Luschny, Generalized Stirling_2 Triangles.

Cf. A157396, A157397, A157398, A157399, A157400, A080510, A157402, A157403, A157404, A157405

T(n,0) = [n = 0] (Iverson notation) and for n > 0 and 1 <= m <= n
T(n,m) = Sum_{a} M(a)|f^a| where a = a_1,..,a_n such that
1*a_1+2*a_2+...+n*a_n = n and max{a_i} = m, M(a) = n!/(a_1!*..*a_n!),
f^a = (f_1/1!)^a_1*..*(f_n/n!)^a_n and f_n = product_{j=0..n-1}(2*j - 1).

A281358 Number of scenarios in the Gift Exchange Game when a gift can be stolen at most 6 times.

Original entry on oeis.org

1, 7, 6427, 216864652, 60790021361170, 79397199549271412737, 350521520018942991464535019, 4247805448772073978048752721163278, 122022975450467092259059357046375920848764, 7449370563518425038119522091529589590475534631830

Offset: 0

N. J. A. Sloane, Jan 25 2017

nonn

The result from the recurrence has been confirmed up to a(63) by using an optimized version of equation (23) in the Applegate-Sloane paper. - Lars Blomberg, Feb 01 2017

Lars Blomberg, Table of n, a(n) for n = 0..88
Moa Apagodu, David Applegate, N. J. A. Sloane, and Doron Zeilberger, Analysis of the Gift Exchange Problem, arXiv:1701.08394 [math.CO], 2017.
Moa Apagodu, David Applegate, N. J. A. Sloane, and Doron Zeilberger, On-Line Appendix I to "Analysis of the gift exchange problem", giving Type D recurrences for G_1(n) through G_15(n) (see A001515, A144416, A144508, A144509, A149187, A281358-A281361)
Moa Apagodu, David Applegate, N. J. A. Sloane, and Doron Zeilberger, On-Line Appendix II to "Analysis of the gift exchange problem", giving Type C recurrences for G_1(n) through G_15(n) (see A001515, A144416, A144508, A144509, A149187, A281358-A281361)
David Applegate and N. J. A. Sloane, The Gift Exchange Problem, arXiv:0907.0513 [math.CO], 2009.

The gift scenarios sequences when a gift can be stolen at most s times, for s = 1..9, are A001515, A144416, A144508, A144509, A149187, A281358, A281359, A281360, A281361.

with(combinat):
b:= proc(n, i, t) option remember; `if`(t*i add(b(k, 7, n), k=0..7*n):
seq(a(n), n=0..12);  # Alois P. Heinz, Feb 01 2017

t[n_, n_] = 1; t[n_ /; n >= 0, k_] /; 0 <= k <= 7*n := t[n, k] = Sum[(1/j!)*Product[k - m, {m, 1, j}]*t[n - 1, k - j - 1], {j, 0, 6}]; t[, ] = 0; a[n_] := Sum[t[n, k], {k, 0, 7*n}]; Table[a[n], {n, 0, 10}] (* Jean-François Alcover, Feb 18 2017 *)

{a(n) = sum(i=n, 7*n, i!*polcoef(sum(j=1, 7, x^j/j!)^n, i))/n!} \\ Seiichi Manyama, May 22 2019

More terms from Lars Blomberg, Feb 01 2017

A281359 Number of scenarios in the Gift Exchange Game when a gift can be stolen at most 7 times.

Original entry on oeis.org

1, 8, 24301, 5165454442, 12845435390707724, 191739533381111401455478, 11834912423104188943497126664597, 2371013832433361706367594400829713564440, 1299618941291522676629215597535104557826094801396, 1716119248126070756229849154290399886241087778087554633612

Offset: 0

N. J. A. Sloane, Jan 25 2017

nonn

Seiichi Manyama, Table of n, a(n) for n = 0..77
Moa Apagodu, David Applegate, N. J. A. Sloane, and Doron Zeilberger, Analysis of the Gift Exchange Problem, arXiv:1701.08394 [math.CO], 2017.
Moa Apagodu, David Applegate, N. J. A. Sloane, and Doron Zeilberger, On-Line Appendix I to "Analysis of the gift exchange problem", giving Type D recurrences for G_1(n) through G_15(n) (see A001515, A144416, A144508, A144509, A149187, A281358-A281361)
Moa Apagodu, David Applegate, N. J. A. Sloane, and Doron Zeilberger, On-Line Appendix II to "Analysis of the gift exchange problem", giving Type C recurrences for G_1(n) through G_15(n) (see A001515, A144416, A144508, A144509, A149187, A281358-A281361)
David Applegate and N. J. A. Sloane, The Gift Exchange Problem, arXiv:0907.0513 [math.CO], 2009.

The gift scenarios sequences when a gift can be stolen at most s times, for s = 1..9, are A001515, A144416, A144508, A144509, A149187, A281358, A281359, A281360, A281361.

with(combinat):
b:= proc(n, i, t) option remember; `if`(t*i add(b(k, 8, n), k=0..8*n):
seq(a(n), n=0..12);  # Alois P. Heinz, Feb 01 2017

t[n_, n_] = 1; t[n_ /; n >= 0, k_] /; 0 <= k <= 8*n := t[n, k] = Sum[(1/j!)*Product[k - m, {m, 1, j}]*t[n - 1, k - j - 1], {j, 0, 7}]; t[, ] = 0; a[n_] := Sum[t[n, k], {k, 0, 8*n}]; Table[a[n], {n, 0, 10}] (* Jean-François Alcover, Feb 18 2017 *)

{a(n) = sum(i=n, 8*n, i!*polcoef(sum(j=1, 8, x^j/j!)^n, i))/n!} \\ Seiichi Manyama, May 22 2019

A281360 Number of scenarios in the Gift Exchange Game when a gift can be stolen at most 8 times.

Original entry on oeis.org

1, 9, 92368, 124762262630, 2774049143394729653, 476872353039366288373555323, 414678423576860263798348331987688320, 1383884737648788823775562903922773021277571568, 14584126149704606223764458141727351569547933381159988406, 419715170056359079715862408734598208208707081189266290220651371206

Offset: 0

N. J. A. Sloane, Jan 25 2017

nonn

More than the usual number of terms are shown in the DATA field because there are the initial values needed for one of the recurrences.

Seiichi Manyama, Table of n, a(n) for n = 0..69
Moa Apagodu, David Applegate, N. J. A. Sloane, and Doron Zeilberger, Analysis of the Gift Exchange Problem, arXiv:1701.08394 [math.CO], 2017.
Moa Apagodu, David Applegate, N. J. A. Sloane, and Doron Zeilberger, On-Line Appendix I to "Analysis of the gift exchange problem", giving Type D recurrences for G_1(n) through G_15(n) (see A001515, A144416, A144508, A144509, A149187, A281358-A281361)
Moa Apagodu, David Applegate, N. J. A. Sloane, and Doron Zeilberger, On-Line Appendix II to "Analysis of the gift exchange problem", giving Type C recurrences for G_1(n) through G_15(n) (see A001515, A144416, A144508, A144509, A149187, A281358-A281361)
David Applegate and N. J. A. Sloane, The Gift Exchange Problem, arXiv:0907.0513 [math.CO], 2009.

The gift scenarios sequences when a gift can be stolen at most s times, for s = 1..9, are A001515, A144416, A144508, A144509, A149187, A281358, A281359, A281360, A281361.

with(combinat):
b:= proc(n, i, t) option remember; `if`(t*i add(b(k, 9, n), k=0..9*n):
seq(a(n), n=0..12);  # Alois P. Heinz, Feb 01 2017

t[n_, n_] = 1; t[n_ /; n >= 0, k_] /; 0 <= k <= 9*n := t[n, k] = Sum[(1/j!)*Product[k - m, {m, 1, j}]*t[n - 1, k - j - 1], {j, 0, 8}]; t[, ] = 0; a[n_] := Sum[t[n, k], {k, 0, 9*n}]; Table[a[n], {n, 0, 10}] (* Jean-François Alcover, Feb 18 2017 *)

{a(n) = sum(i=n, 9*n, i!*polcoef(sum(j=1, 9, x^j/j!)^n, i))/n!} \\ Seiichi Manyama, May 22 2019

A281361 Number of scenarios in the Gift Exchange Game when a gift can be stolen at most 9 times.

Original entry on oeis.org

1, 10, 352705, 3047235458767, 609542744597785306189, 1214103036523322674154687139158, 14963835327495031822418126706099787884130, 836883118002221273912672040462907783367741190535388, 170589804359366329173961838612841486616626580885839826818966688, 107640669875812795238625627484701500354901860426640161278022882392148747562, 185260259482556646382994900799988470488841686941141661692183483756531004879305895810561

Offset: 0

N. J. A. Sloane, Jan 25 2017

nonn

More than the usual number of terms are shown in the DATA field because there are the initial values needed for one of the recurrences.

Seiichi Manyama, Table of n, a(n) for n = 0..63
Moa Apagodu, David Applegate, N. J. A. Sloane, and Doron Zeilberger, Analysis of the Gift Exchange Problem, arXiv:1701.08394 [math.CO], 2017.
Moa Apagodu, David Applegate, N. J. A. Sloane, and Doron Zeilberger, On-Line Appendix I to "Analysis of the gift exchange problem", giving Type D recurrences for G_1(n) through G_15(n) (see A001515, A144416, A144508, A144509, A149187, A281358-A281361)
Moa Apagodu, David Applegate, N. J. A. Sloane, and Doron Zeilberger, On-Line Appendix II to "Analysis of the gift exchange problem", giving Type C recurrences for G_1(n) through G_15(n) (see A001515, A144416, A144508, A144509, A149187, A281358-A281361)
David Applegate and N. J. A. Sloane, The Gift Exchange Problem, arXiv:0907.0513 [math.CO], 2009.

The gift scenarios sequences when a gift can be stolen at most s times, for s = 1..9, are A001515, A144416, A144508, A144509, A149187, A281358, A281359, A281360, A281361.

with(combinat):
b:= proc(n, i, t) option remember; `if`(t*i add(b(k, 10, n), k=0..10*n):
seq(a(n), n=0..12);  # Alois P. Heinz, Feb 01 2017

t[n_, n_] = 1; t[n_ /; n >= 0, k_] /; 0 <= k <= 10*n := t[n, k] = Sum[(1/j!)*Product[k - m, {m, 1, j}]*t[n - 1, k - j - 1], {j, 0, 9}]; t[, ] = 0; a[n_] := Sum[t[n, k], {k, 0, 10*n}]; Table[a[n], {n, 0, 11}] (* Jean-François Alcover, Feb 18 2017 *)

{a(n) = sum(i=n, 10*n, i!*polcoef(sum(j=1, 10, x^j/j!)^n, i))/n!} \\ Seiichi Manyama, May 22 2019

A028575 Row sums of triangle A011801.

Original entry on oeis.org

1, 5, 49, 721, 14177, 349141, 10334689, 357361985, 14137664833, 629779342213, 31195027543505, 1700812505769169, 101218448336028193, 6528869281965115541, 453720852957751220353, 33796334125623555379969, 2686138908337714715560577, 226908450494953996837748869

Offset: 1

Wolfdieter Lang

Vincenzo Librandi, Table of n, a(n) for n = 1..200
Wolfdieter Lang, On generalizations of Stirling number triangles, J. Integer Seqs., Vol. 3 (2000), #00.2.4.

Sequences with e.g.f. exp(1-(1-m*x)^(1/m)) - 1: A000012 (m=1), A001515 (m=2), A015735 (m=3), A016036 (m=4), this sequence (m=5), A028844 (m=6).

Cf. A011801.

R:=PowerSeriesRing(Rationals(), 30); Coefficients(R!(Laplace( Exp(1-(1-5*x)^(1/5)) - 1 ))); // G. C. Greubel, Oct 02 2023

Rest[With[{nn=20},CoefficientList[Series[Exp[1-(1-5x)^(1/5)]-1, {x,0,nn}], x] Range[0,nn]!]] (* Harvey P. Dale, Aug 02 2016 *)

def A028575_list(prec):
    P. = PowerSeriesRing(QQ, prec)
    return P( exp(1-(1-5*x)^(1/5)) -1 ).egf_to_ogf().list()
a=A028575_list(40); a[1:] # G. C. Greubel, Oct 02 2023

E.g.f.: exp(1 - (1-5*x)^(1/5)) - 1.
a(n) = D^n(exp(x)) evaluated at x = 0, where D is the operator 1/(1-x)^4*d/dx. Cf. A001515, A015735 and A016036. - Peter Bala, Nov 25 2011
D-finite with recurrence: a(n) -20*(n-3)*a(n-1) +30*(5*n^2-35*n +62)*a(n-2) -100*(n-4)*(5*n^2-40*n+81)*a(n-3) +(5*n-22)*(5*n-21)*(5*n-24)*(5*n-23)*a(n-4) -a(n-5) = 0. - R. J. Mathar, Jan 28 2020
From Seiichi Manyama, Jan 20 2025: (Start)
a(n) = Sum_{k=0..n} (-1)^k * 5^(n-k) * |Stirling1(n,k)| * A000587(k).
a(n) = e * (-5)^n * n! * Sum_{k>=0} (-1)^k * binomial(k/5,n)/k!. (End)

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cp's OEIS Frontend

A149187 a(n) = total number of partitions of [1, 2, ..., k] into exactly n blocks, each of size 1, 2, ..., 6, for 0 <= k <= 6n.

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A132062 Sheffer triangle (1,1-sqrt(1-2*x)). Extended Bessel triangle A001497.

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A144301 a(0) = a(1) = 1; thereafter a(n) = (2*n-3)*a(n-1) + a(n-2).

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A144502 Square array read by antidiagonals upwards: T(n,k) is the number of scenarios for the gift exchange problem in which each gift can be stolen at most once, when there are n gifts in the pool and k gifts (not yet frozen) in peoples' hands.

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A157401 A partition product of Stirling_2 type [parameter k = 1] with biggest-part statistic (triangle read by rows).

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A281358 Number of scenarios in the Gift Exchange Game when a gift can be stolen at most 6 times.

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A281359 Number of scenarios in the Gift Exchange Game when a gift can be stolen at most 7 times.

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A144301 a(0) = a(1) = 1; thereafter a(n) = (2n-3)a(n-1) + a(n-2).