A102290
Total number of even lists in all sets of lists, cf. A000262.
Original entry on oeis.org
0, 0, 2, 6, 60, 380, 3990, 37002, 450296, 5373720, 76018410, 1096730030, 17814654132, 299645294676, 5511836578430, 105550556136690, 2171244984679920, 46545825736022192, 1059273836225051346, 25100215228045842390, 626204775725372971820, 16239127347086448236460
Offset: 0
-
l:= func< n,b | Evaluate(LaguerrePolynomial(n), b) >;
[0,0]cat[Factorial(n)*(&+[(-1)^(n+j)*l(j,-1): j in [0..n-2]]): n in [2..30]]; // G. C. Greubel, Mar 09 2021
-
Gser:=series(x^2*exp(x/(1-x))/(1-x^2),x=0,22):seq(n!*coeff(Gser,x^n),n=1..21); # Emeric Deutsch
# second Maple program:
b:= proc(n) option remember; `if`(n=0, [1, 0], add(
(p-> p+`if`(j::even, [0, p[1]], 0))(b(n-j)*
binomial(n-1, j-1)*j!), j=1..n))
end:
a:= n-> b(n, 0)[2]:
seq(a(n), n=0..25); # Alois P. Heinz, May 10 2016
-
Rest[CoefficientList[Series[x^2/(1-x^2)*E^(x/(1-x)), {x, 0, 20}], x]* Range[0, 20]!] (* Vaclav Kotesovec, Sep 29 2013 *)
Table[If[n<2, 0, n!*Sum[(-1)^(n-j)*LaguerreL[j, -1], {j,0,n-2}]], {n,0,30}] (* G. C. Greubel, Mar 09 2021 *)
-
[0,0]+[factorial(n)*sum((-1)^(n+j)*gen_laguerre(j,0,-1) for j in (0..n-2)) for n in (2..30)] # G. C. Greubel, Mar 09 2021
A152151
Riordan array [(1-x)exp(x/(1-x)),x].
Original entry on oeis.org
1, 0, 1, 1, 0, 1, 4, 3, 0, 1, 21, 16, 6, 0, 1, 136, 105, 40, 10, 0, 1, 1045, 816, 315, 80, 15, 0, 1, 9276, 7315, 2856, 735, 140, 21, 0, 1, 93289, 74208, 29260, 7616, 1470, 224, 28, 0, 1, 1047376, 839601, 333936, 87780, 17136, 2646, 336, 36
Offset: 0
Triangle begins
1,
0, 1,
1, 0, 1,
4, 3, 0, 1,
21, 16, 6, 0, 1,
136, 105, 40, 10, 0, 1,
1045, 816, 315, 80, 15, 0, 1,
9276, 7315, 2856, 735, 140, 21, 0, 1,
with production matrix which begins
0, 1,
1, 0, 1,
4, 2, 0, 1,
18, 12, 3, 0, 1,
96, 72, 24, 4, 0, 1,
600, 480, 180, 40, 5, 0, 1;
4320, 3600, 1440, 360, 60, 6, 1
with e.g.f. exp(x*t)(t+1/(1-x)^2).
Original entry on oeis.org
1, 2, 5, 18, 91, 592, 4643, 42276, 436629, 5033182, 63974273, 888047414, 13358209647, 216334610860, 3751352135263, 69325155322184, 1359759373992105, 28206375825238458, 616839844140642301, 14181213537729200474, 341879141423814854915, 8623032181189674581256
Offset: 0
a(20) = 1 + 1 + 3 + 13 + 73 + 501 + 4051 + 37633 + 394353 + 4596553 + 58941091 + 824073141 + 12470162233 + 202976401213 + 3535017524403 + 65573803186921 + 1290434218669921 + 26846616451246353 + 588633468315403843 + 13564373693588558173 + 327697927886085654441.
-
l:= func< n,b | Evaluate(LaguerrePolynomial(n), b) >;
[n eq 0 select 1 else 1 + (&+[ Factorial(j)*( l(j,-1) - l(j-1,-1) ): j in [1..n]]): n in [0..25]]; // G. C. Greubel, Mar 09 2021
-
b:= proc(n) option remember; `if`(n=0, 1, add(
b(n-j)*j!*binomial(n-1, j-1), j=1..n))
end:
a:= proc(n) option remember; b(n)+`if`(n>0, a(n-1), 0) end:
seq(a(n), n=0..25); # Alois P. Heinz, May 11 2016
-
With[{m = 25}, CoefficientList[Exp[x/(1-x)] + O[x]^m, x] Range[0, m-1]!// Accumulate] (* Jean-François Alcover, Nov 21 2020 *)
Table[1 +Sum[j!*(LaguerreL[j, -1] -LaguerreL[j-1, -1]), {j,n}], {n,0,30}] (* G. C. Greubel, Mar 09 2021 *)
-
[1 + sum(factorial(j)*(gen_laguerre(j,0,-1) - gen_laguerre(j-1,0,-1)) for j in (1..n)) for n in (0..30)] # G. C. Greubel, Mar 09 2021
A300159
Number of ways of converting one set of lists containing n elements to another set of lists containing n elements by removing the last element from one of the lists and either appending it to an existing list or treating it as a new list.
Original entry on oeis.org
0, 0, 4, 30, 240, 2140, 21300, 235074, 2853760, 37819800, 543445380, 8416452550, 139753069104, 2476581106740, 46648575724660, 930581784937770, 19597766647728000, 434455097953799344, 10112163333554834820, 246539064280189932270, 6282671083849941925360
Offset: 0
a(0) = 0 since for 0 lists, 0 conversions are possible.
a(1) = 0 since for the 1 set of 1 list of length 1, there exist no possible conversions.
a(2) = 4 since for the 2 sets of 1 list of length 2, there exists only 1 conversion, and for the 1 set of 2 lists of length 1, there exist 2 conversions.
a(3) = 30 since for the 6 sets of 1 list of length 3, there exists 1 conversion, for the 6 sets of 1 list of length 2 and 1 list of length 1, there exist 3 conversions, and for the 1 set of 3 lists of length 1, there exists 6 conversions.
Extends
A000262 to count conversions in addition to sets of lists.
-
l:= func< n,b | Evaluate(LaguerrePolynomial(n,1), b) >;
[0,0,4]cat[Factorial(n)*( 2*l(n-2,-1) - l(n-3,-1) ): n in [3..30]]; // G. C. Greubel, Mar 09 2021
-
b:= proc(n, t, c) option remember; `if`(n=0, t^2-c, add(j!*
binomial(n-1, j-1)*b(n-j, t+1, c+`if`(j=1, 1, 0)), j=1..n))
end:
a:= n-> b(n, 0$2):
seq(a(n), n=0..25); # Alois P. Heinz, Mar 05 2018
# second Maple program:
a:= proc(n) option remember; `if`(n<6, [0$2, 4, 30, 240, 2140][n+1],
(n*(2*n^2-13*n+16)*a(n-1)-n*(n-1)*(n-3)*(n-4)*a(n-2))/((n-2)*(n-5)))
end:
seq(a(n), n=0..25); # Alois P. Heinz, Mar 05 2018
-
(* First program *)
b[n_, t_, c_]:= b[n,t,c]= If[n==0, t^2 -c, Sum[j! Binomial[n-1, j-1]b[n-j,t+1,c + If[j==1, 1, 0]], {j,n}]];
a[n_]:= b[n, 0, 0];
a/@ Range[0, 25] (* Jean-François Alcover, Nov 24 2020, after Alois P. Heinz *)
(* Second program *)
Table[If[n<2, 0, n!*(2*LaguerreL[n-2,1,-1] -LaguerreL[n-3,1,-1])], {n,0,30}] (* G. C. Greubel, Mar 09 2021 *)
-
[0,0,4]+[factorial(n)*(2*gen_laguerre(n-2,1,-1) - gen_laguerre(n-3,0,-1)) for n in (3..30)] # G. C. Greubel, Mar 09 2021
A316666
Number of simple relaxed compacted binary trees of right height at most one with no sequences on level 1 and no final sequences on level 0.
Original entry on oeis.org
1, 0, 1, 3, 15, 87, 597, 4701, 41787, 413691, 4512993, 53779833, 695000919, 9680369943, 144560191149, 2303928046437, 39031251610227, 700394126116851, 13270625547477177, 264748979672169681, 5547121478845459983, 121784530649198053263, 2795749225338111831429, 66981491857058929294653
Offset: 0
- G. C. Greubel, Table of n, a(n) for n = 0..448
- Antoine Genitrini, Bernhard Gittenberger, Manuel Kauers and Michael Wallner, Asymptotic Enumeration of Compacted Binary Trees, arXiv:1703.10031 [math.CO], 2017.
- Michael Wallner, A bijection of plane increasing trees with relaxed binary trees of right height at most one, arXiv:1706.07163 [math.CO], 2017.
-
m:=25; R:=PowerSeriesRing(Rationals(), m); b:=Coefficients(R!( (3*Exp(-x) + x-2)/(1-x)^2 )); [Factorial(n-1)*b[n]: n in [1..m]]; // G. C. Greubel, Dec 12 2018
-
aseq := n-> 3*round((n+2)*n!/exp(1))-(n+2)*n!: bseq := n-> (n+2)*n!- 2* round((n+2)*n!/exp(1)): s := (a,b,n)-> a*aseq(n) + b*bseq( n): seq(s(1,0,n),n = 0..20); # Gary Detlefs, Dec 11 2018
-
terms = 24;
CoefficientList[(3E^-z+z-2)/(1-z)^2 + O[z]^terms, z] Range[0, terms-1]! (* Jean-François Alcover, Sep 14 2018 *)
-
Vec(serlaplace((3*exp(-x + O(x^25)) + x - 2)/(1 - x)^2)) \\ Andrew Howroyd, Jul 10 2018
A317096
Expansion of e.g.f. ((1 - x)/(1 - 2*x))*exp(x/(x - 1)).
Original entry on oeis.org
1, 0, 1, 8, 69, 704, 8485, 118824, 1900297, 34191296, 683657001, 15038537480, 360903291661, 9383240195328, 262727926084429, 7881806223689384, 252217461390469905, 8575390623429206144, 308714050531090308817, 11731134397549023854856, 469245396934886909801941, 19708307298664103361642560
Offset: 0
-
R:=PowerSeriesRing(Rationals(), 26);
Coefficients(R!(Laplace( ((1-x)/(1-2*x))*Exp(x/(x-1)) ))); // G. C. Greubel, Mar 09 2021
-
a:=series(exp(x/(x - 1))*(1 - x)/(1 - 2*x), x=0, 22): seq(n!*coeff(a, x, n), n=0..21); # Paolo P. Lava, Mar 26 2019
-
nmax = 21; CoefficientList[Series[Exp[x/(x - 1)] (1 - x)/(1 - 2 x), {x, 0, nmax}], x] Range[0, nmax]!
Table[Sum[Binomial[n - 1, k - 1] Subfactorial[k] n!/k!, {k, 0, n}], {n, 0, 21}]
A317096[n_]:= A317096[n]= n!*(LaguerreL[n,1] + Sum[2^(n-j-2)*LaguerreL[j,1], {j,0, n-2}]); Table[A317096[n], {n,0,25}] (* G. C. Greubel, Mar 09 2021 *)
-
def A317096(n): return factorial(n)*( gen_laguerre(n,0,1) + sum(2^(n-j-2)*gen_laguerre(j,0,1) for j in (0..n-2)) )
[A317096(n) for n in (0..25)] # G. C. Greubel, Mar 09 2021
A323770
Expansion of e.g.f. x*(2 - x)*exp(x/(1 - x))/(2*(1 - x)^2).
Original entry on oeis.org
0, 1, 5, 30, 214, 1775, 16791, 178360, 2101100, 27172269, 382566025, 5823044546, 95253119490, 1666020561595, 31019392831259, 612430207741500, 12778091116288216, 280893425932078745, 6487870112636577165, 157066777096248548134, 3976727555939887035950, 105087648979005066820551
Offset: 0
-
[n eq 0 select 0 else (&+[Binomial(n-1,k)*Binomial(k+2,2)* Factorial(n)/Factorial(k+1): k in [0..n-1]]): n in [0..20]]; // G. C. Greubel, Mar 05 2021
-
seq(n!*coeff(series(x*(2-x)*exp(x/(1-x))/(2*(1-x)^2),x=0,22),x,n),n=0..21); # Paolo P. Lava, Jan 29 2019
-
nmax = 21; CoefficientList[Series[x (2 - x) Exp[x/(1 - x)]/(2 (1 - x)^2), {x, 0, nmax}], x] Range[0, nmax]!
Table[Sum[Binomial[n - 1, k - 1] Binomial[k + 1, 2] n!/k!, {k, 0, n}], {n, 0, 21}]
-
[0]+[sum(binomial(n-1,k)*binomial(k+2,2)*factorial(n)/factorial(k+1) for k in (0..n-1)) for n in [1..20]] # G. C. Greubel, Mar 05 2021
A347340
E.g.f.: exp( exp(exp(x) - 1) - exp(x) ).
Original entry on oeis.org
1, 0, 1, 4, 17, 91, 587, 4327, 35604, 323316, 3210600, 34574453, 400893066, 4975247460, 65755573847, 921535225267, 13643496840808, 212688569520955, 3480978391442106, 59657975022473437, 1068151956803180295, 19937983367649562025, 387243759600707804811, 7812456801157894913964
Offset: 0
-
g:= proc(n) option remember; `if`(n=0, 1,
add(g(n-j)*binomial(n-1, j-1), j=2..n))
end:
b:= proc(n, m) option remember; `if`(n=0,
g(m), m*b(n-1, m)+b(n-1, m+1))
end:
a:= n-> b(n, 0):
seq(a(n), n=0..23); # Alois P. Heinz, Aug 27 2021
# second Maple program:
b:= proc(n, t) option remember; `if`(n=0, 1, add(b(n-j, t)*
`if`(t=0, 1, b(j, 0)-1)*binomial(n-1, j-1), j=1..n))
end:
a:= n-> b(n, 1):
seq(a(n), n=0..23); # Alois P. Heinz, Sep 02 2021
-
nmax = 23; CoefficientList[Series[Exp[Exp[Exp[x] - 1] - Exp[x]], {x, 0, nmax}], x] Range[0, nmax]!
a[0] = 1; a[n_] := a[n] = Sum[Binomial[n - 1, k - 1] (BellB[k] - 1) a[n - k], {k, 1, n}]; Table[a[n], {n, 0, 23}]
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my(x='x+O('x^25)); Vec(serlaplace(exp(exp(exp(x)-1)-exp(x)))) \\ Michel Marcus, Aug 27 2021
A358631
Irregular table T(n, k), n >= 0, k > 0, read by rows of extended (due to binary expansion of n) Stirling numbers of the first kind.
Original entry on oeis.org
1, 1, 2, 3, 1, 4, 5, 1, 6, 11, 6, 1, 6, 7, 1, 12, 20, 9, 1, 18, 26, 9, 1, 24, 50, 35, 10, 1, 8, 9, 1, 18, 29, 12, 1, 30, 41, 12, 1, 48, 94, 59, 14, 1, 36, 47, 12, 1, 72, 130, 71, 14, 1, 96, 154, 71, 14, 1, 120, 274, 225, 85, 15, 1, 10, 11, 1, 24, 38, 15, 1, 42
Offset: 0
Irregular table begins:
1, 1;
2, 3, 1;
4, 5, 1;
6, 11, 6, 1;
6, 7, 1;
12, 20, 9, 1;
18, 26, 9, 1;
24, 50, 35, 10, 1;
8, 9, 1;
18, 29, 12, 1;
30, 41, 12, 1;
48, 94, 59, 14, 1;
36, 47, 12, 1;
72, 130, 71, 14, 1;
96, 154, 71, 14, 1;
120, 274, 225, 85, 15, 1;
-
b1(n)=if(n>0, my(A=n - 2^logint(n, 2)); if(A>0, logint(A, 2) + 1))
b2(n)=if(n>0, my(A=b1(3*2^logint(n, 2) - n - 1)); n + if(A>0, 2^(A-1)))
P(n,k)=if(n==0 || k==1, (n==0 && k<3) + (k==1 && n>0), my(L=logint(n, 2), A=n - 2^L); (hammingweight(A) + 2)*P(A, k-1)*(L - b1(n) + 1) + P(b2(A), k))
T(n, k)=my(A=hammingweight(n)); if(k<=(A + 2), P(n, A - k + 3))
A361893
Triangle read by rows. T(n, k) = n! * binomial(n - 1, k - 1) / (n - k)!.
Original entry on oeis.org
1, 0, 1, 0, 2, 2, 0, 3, 12, 6, 0, 4, 36, 72, 24, 0, 5, 80, 360, 480, 120, 0, 6, 150, 1200, 3600, 3600, 720, 0, 7, 252, 3150, 16800, 37800, 30240, 5040, 0, 8, 392, 7056, 58800, 235200, 423360, 282240, 40320, 0, 9, 576, 14112, 169344, 1058400, 3386880, 5080320, 2903040, 362880
Offset: 0
Triangle T(n, k) starts:
[0] 1;
[1] 0, 1;
[2] 0, 2, 2;
[3] 0, 3, 12, 6;
[4] 0, 4, 36, 72, 24;
[5] 0, 5, 80, 360, 480, 120;
[6] 0, 6, 150, 1200, 3600, 3600, 720;
[7] 0, 7, 252, 3150, 16800, 37800, 30240, 5040;
[8] 0, 8, 392, 7056, 58800, 235200, 423360, 282240, 40320;
[9] 0, 9, 576, 14112, 169344, 1058400, 3386880, 5080320, 2903040, 362880;
-
A361893 := (n, k) -> n!*binomial(n - 1, k - 1)/(n - k)!:
seq(seq(A361893(n,k), k = 0..n), n = 0..9);
# Using the egf.:
egf := 1 + (x*y/(1 - x*y))*exp(y/(1 - x*y)): ser := series(egf, y, 10):
poly := n -> convert(n!*expand(coeff(ser, y, n)), polynom):
row := n -> seq(coeff(poly(n), x, k), k = 0..n): seq(print(row(n)), n = 0..6);
Comments