cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

Showing 1-5 of 5 results.

A048994 Triangle of Stirling numbers of first kind, s(n,k), n >= 0, 0 <= k <= n.

Original entry on oeis.org

1, 0, 1, 0, -1, 1, 0, 2, -3, 1, 0, -6, 11, -6, 1, 0, 24, -50, 35, -10, 1, 0, -120, 274, -225, 85, -15, 1, 0, 720, -1764, 1624, -735, 175, -21, 1, 0, -5040, 13068, -13132, 6769, -1960, 322, -28, 1, 0, 40320, -109584, 118124, -67284, 22449, -4536, 546, -36, 1, 0, -362880, 1026576, -1172700, 723680, -269325, 63273, -9450, 870, -45, 1
Offset: 0

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Author

Keywords

Comments

The unsigned numbers are also called Stirling cycle numbers: |s(n,k)| = number of permutations of n objects with exactly k cycles.
Mirror image of the triangle A054654. - Philippe Deléham, Dec 30 2006
Also the triangle gives coefficients T(n,k) of x^k in the expansion of C(x,n) = (a(k)*x^k)/n!. - Mokhtar Mohamed, Dec 04 2012
From Wolfdieter Lang, Nov 14 2018: (Start)
This is the Sheffer triangle of Jabotinsky type (1, log(1 + x)). See the e.g.f. of the triangle below.
This is the inverse Sheffer triangle of the Stirling2 Sheffer triangle A008275.
The a-sequence of this Sheffer triangle (see a W. Lang link in A006232)
is from the e.g.f. A(x) = x/(exp(x) -1) a(n) = Bernoulli(n) = A027641(n)/A027642(n), for n >= 0. The z-sequence vanishes.
The Boas-Buck sequence for the recurrences of columns has o.g.f. B(x) = Sum_{n>=0} b(n)*x^n = 1/((1 + x)*log(1 + x)) - 1/x. b(n) = (-1)^(n+1)*A002208(n+1)/A002209(n+1), b = {-1/2, 5/12, -3/8, 251/720, -95/288, 19087/60480,...}. For the Boas-Buck recurrence of Riordan and Sheffer triangles see the Aug 10 2017 remark in A046521, adapted to the Sheffer case, also for two references. See the recurrence and example below. (End)
Let G(n,m,k) be the number of simple labeled graphs on [n] with m edges and k components. Then T(n,k) = Sum (-1)^m*G(n,m,k). See the Read link below. Equivalently, T(n,k) = Sum mu(0,p) where the sum is over all set partitions p of [n] containing k blocks and mu is the Moebius function in the incidence algebra associated to the set partition lattice on [n]. - Geoffrey Critzer, May 11 2024

Examples

			Triangle begins:
  n\k 0     1       2       3      4      5      6    7    8   9 ...
  0   1
  1   0     1
  2   0    -1       1
  3   0     2      -3       1
  4   0    -6      11      -6      1
  5   0    24     -50      35    -10      1
  6   0  -120     274    -225     85    -15      1
  7   0   720   -1764    1624   -735    175    -21    1
  8   0 -5040   13068  -13132   6769  -1960    322  -28    1
  9   0 40320 -109584  118124 -67284  22449  -4536  546  -36   1
  ... - _Wolfdieter Lang_, Aug 22 2012
------------------------------------------------------------------
From _Wolfdieter Lang_, Nov 14 2018: (Start)
Recurrence: s(5,2)= s(4, 1) - 4*s(4, 2) = -6 - 4*11 = -50.
Recurrence from the a- and z-sequences: s(6, 3) = 2*(1*1*(-50) + 3*(-1/2)*35 + 6*(1/6)*(-10) + 10*0*1) = -225.
Boas-Buck recurrence for column k = 3, with b = {-1/2, 5/12, -3/8, ...}:
s(6, 3) = 6!*((-3/8)*1/3! + (5/12)*(-6)/4! + (-1/2)*35/5!) = -225. (End)
		

References

  • M. Abramowitz and I. A. Stegun, eds., Handbook of Mathematical Functions, National Bureau of Standards Applied Math. Series 55, 1964 (and various reprintings), p. 833.
  • L. Comtet, Advanced Combinatorics, Reidel, 1974; Chapter V, also p. 310.
  • J. H. Conway and R. K. Guy, The Book of Numbers, Copernicus Press, NY, 1996, p. 93.
  • F. N. David, M. G. Kendall and D. E. Barton, Symmetric Function and Allied Tables, Cambridge, 1966, p. 226.
  • R. L. Graham, D. E. Knuth and O. Patashnik, Concrete Mathematics. Addison-Wesley, Reading, MA, 1990, p. 245.
  • J. Riordan, An Introduction to Combinatorial Analysis, p. 48.

Crossrefs

See especially A008275 which is the main entry for this triangle. A132393 is an unsigned version, and A008276 is another version.
A000142(n) = Sum_{k=0..n} |s(n, k)| for n >= 0.
Row sums give A019590(n+1).

Programs

  • Haskell
    a048994 n k = a048994_tabl !! n !! k
    a048994_row n = a048994_tabl !! n
    a048994_tabl = map fst $ iterate (\(row, i) ->
    (zipWith (-) ([0] ++ row) $ map (* i) (row ++ [0]), i + 1)) ([1], 0)
    -- Reinhard Zumkeller, Mar 18 2013
  • Maple
    A048994:= proc(n,k) combinat[stirling1](n,k) end: # R. J. Mathar, Feb 23 2009
    seq(print(seq(coeff(expand(k!*binomial(x,k)),x,i),i=0..k)),k=0..9); # Peter Luschny, Jul 13 2009
    A048994_row := proc(n) local k; seq(coeff(expand(pochhammer(x-n+1,n)), x,k), k=0..n) end: # Peter Luschny, Dec 30 2010
  • Mathematica
    Table[StirlingS1[n, m], {n, 0, 9}, {m, 0, n}] (* Peter Luschny, Dec 30 2010 *)
  • Maxima
    create_list(stirling1(n,k),n,0,12,k,0,n); /* Emanuele Munarini, Mar 11 2011 */
    
  • PARI
    a(n,k) = if(k<0 || k>n,0, if(n==0,1,(n-1)*a(n-1,k)+a(n-1,k-1)))
    
  • PARI
    trg(nn)=for (n=0, nn-1, for (k=0, n, print1(stirling(n,k,1), ", ");); print();); \\ Michel Marcus, Jan 19 2015
    

Formula

s(n, k) = A008275(n,k) for n >= 1, k = 1..n; column k = 0 is {1, repeat(0)}.
s(n, k) = s(n-1, k-1) - (n-1)*s(n-1, k), n, k >= 1; s(n, 0) = s(0, k) = 0; s(0, 0) = 1.
The unsigned numbers a(n, k)=|s(n, k)| satisfy a(n, k)=a(n-1, k-1)+(n-1)*a(n-1, k), n, k >= 1; a(n, 0) = a(0, k) = 0; a(0, 0) = 1.
Triangle (signed) = [0, -1, -1, -2, -2, -3, -3, -4, -4, ...] DELTA [1, 0, 1, 0, 1, 0, 1, 0, ...]; Triangle(unsigned) = [0, 1, 1, 2, 2, 3, 3, 4, 4, ...] DELTA [1, 0, 1, 0, 1, 0, 1, 0, ...]; where DELTA is Deléham's operator defined in A084938.
Sum_{k=0..n} (-m)^(n-k)*s(n, k) = A000142(n), A001147(n), A007559(n), A007696(n), ... for m = 1, 2, 3, 4, ... .- Philippe Deléham, Oct 29 2005
A008275*A007318 as infinite lower triangular matrices. - Gerald McGarvey, Aug 20 2009
T(n,k) = n!*[x^k]([t^n]exp(x*log(1+t))). - Peter Luschny, Dec 30 2010, updated Jun 07 2020
From Wolfdieter Lang, Nov 14 2018: (Start)
Recurrence from the Sheffer a-sequence (see a comment above): s(n, k) = (n/k)*Sum_{j=0..n-k} binomial(k-1+j, j)*Bernoulli(j)*s(n-1, k-1+j), for n >= 1 and k >= 1, with s(n, 0) = 0 if n >= 1, and s(0,0) = 1.
Boas-Buck type recurrence for column k: s(n, k) = (n!*k/(n - k))*Sum_{j=k..n-1} b(n-1-j)*s(j, k)/j!, for n >= 1 and k = 0..n-1, with input s(n, n) = 1. For sequence b see the Boas-Buck comment above. (End)
T(n,k) = Sum_{j=k..n} (-1)^(n-j)*A271705(n,j)*A216294(j,k). - Mélika Tebni, Feb 23 2023

Extensions

Offset corrected by R. J. Mathar, Feb 23 2009
Formula corrected by Philippe Deléham, Sep 10 2009

A062147 Row sums of unsigned triangle A062137 (generalized a=3 Laguerre).

Original entry on oeis.org

1, 5, 31, 229, 1961, 19081, 207775, 2501801, 32989969, 472630861, 7307593151, 121247816845, 2148321709561, 40476722545169, 807927483311551, 17028146983530961, 377844723929464865, 8803698102396787861, 214877019857456672479, 5482159931449737760181
Offset: 0

Views

Author

Wolfdieter Lang, Jun 19 2001

Keywords

Crossrefs

Programs

  • Magma
    [Factorial(n)*(&+[Binomial(n+3,n-m)/Factorial(m): m in [0..n]]): n in [0..30]]; // G. C. Greubel, Feb 06 2018
    
  • Maple
    A062147 := n -> n!*simplify(LaguerreL(n,3,-1), 'LaguerreL');
    seq(A062147(n), n = 0 .. 30); # G. C. Greubel, Mar 10 2021
  • Mathematica
    Table[Sum[n!*Binomial[n+3,n-k]/k!,{k,0,n}],{n,0,20}]
    (* or *)
    Table[n!*SeriesCoefficient[E^(x/(1-x))/(1-x)^4,{x,0,n}],{n,0,20}] (* Vaclav Kotesovec, Oct 11 2012 *)
  • PARI
    my(x='x+O('x^66)); Vec(serlaplace(exp(x/(1-x))/(1-x)^4)) \\ Joerg Arndt, May 06 2013
    
  • PARI
    a(n) = vecsum(apply(abs,Vec(n!*pollaguerre(n, 3)))); \\ Michel Marcus, Feb 06 2021
    
  • Sage
    [factorial(n)*gen_laguerre(n, 3, -1) for n in (0..30)] # G. C. Greubel, Mar 10 2021

Formula

E.g.f.: exp(x/(1-x))/(1-x)^4.
a(n) = Sum_{m=0..n} n!*binomial(n+3, n-m)/m!.
a(n) = (2*n+3)*a(n-1) - (n-1)*(n+2)*a(n-2). - Vaclav Kotesovec, Oct 11 2012
a(n) ~ exp(2*sqrt(n)-n-1/2)*n^(n+7/4)/sqrt(2). - Vaclav Kotesovec, Oct 11 2012
a(n) = n!*LaguerreL(n, 3, -1). - G. C. Greubel, Mar 10 2021

A062192 Row sums of unsigned triangle A062138 (generalized a=5 Laguerre).

Original entry on oeis.org

1, 7, 57, 529, 5509, 63591, 805597, 11109337, 165625929, 2654025319, 45481765921, 829903882017, 16062421776397, 328634683136839, 7086337847838789, 160604998959958441, 3816483607166825617
Offset: 0

Views

Author

Wolfdieter Lang, Jun 19 2001

Keywords

Crossrefs

Programs

  • Magma
    [Factorial(n)*(&+[Binomial(n+5,n-m)/Factorial(m): m in [0..n]]): n in [0..30]]; // G. C. Greubel, Feb 06 2018
    
  • Maple
    A062192:= n -> n!*simplify(LaguerreL(n,5,-1), 'LaguerreL');
    seq(A062192(n), n = 0 .. 30); # G. C. Greubel, Mar 10 2021
  • Mathematica
    Table[Sum[n! Binomial[n+5,n-m]/m!,{m,0,n}],{n,0,20}] (* Harvey P. Dale, Apr 11 2012 *)
  • PARI
    { f=1; for (n=0, 100, if (n>1, f*=n); a=f*binomial(n+5, n); g=1; a+=sum(m=1, n, f*binomial(n+5, n-m)/g*=m); write("b062192.txt", n, " ", a) ) } \\ Harry J. Smith, Aug 02 2009
    
  • PARI
    my(x='x+O('x^30)); Vec(serlaplace(exp(x/(1-x))/(1-x)^6)) \\ G. C. Greubel, Feb 06 2018
    
  • PARI
    a(n) = vecsum(apply(abs, Vec(n!*pollaguerre(n, 5)))); \\ Michel Marcus, Feb 06 2021
    
  • Sage
    [factorial(n)*gen_laguerre(n, 5, -1) for n in (0..30)] # G. C. Greubel, Mar 10 2021

Formula

E.g.f.: exp(x/(1-x))/(1-x)^6.
a(n) = Sum_{m=0..n} n!*binomial(n+5, n-m)/m!.
a(n) = (2*n+5)*a(n-1) - (n-1)*(n+4)*a(n-2). - Vaclav Kotesovec, Oct 11 2012
a(n) ~ exp(2*sqrt(n)-n-1/2)*n^(n+11/4)/sqrt(2). - Vaclav Kotesovec, Oct 11 2012
a(n) = n!*LaguerreL(n, 5, -1). - G. C. Greubel, Mar 10 2021

A062266 Row sums of unsigned triangle A062140 (generalized a=4 Laguerre).

Original entry on oeis.org

1, 6, 43, 358, 3393, 36046, 424051, 5470158, 76751233, 1163391958, 18941512731, 329604456886, 6103575192193, 119823200043678, 2485452283923043, 54309931242376606, 1246803623807490561, 29999359707124127398, 754865494585690965643, 19824604328577866107398
Offset: 0

Views

Author

Wolfdieter Lang, Jun 19 2001

Keywords

Crossrefs

Programs

  • Magma
    [(&+[Factorial(n)*Binomial(n+4,n-m)/Factorial(m): m in [0..n]]): n in [0..20]]; // G. C. Greubel, Feb 06 2018
    
  • Maple
    A062266:= n -> n!*simplify(LaguerreL(n,4,-1), 'LaguerreL');
    seq(A062266(n), n = 0 .. 30); # G. C. Greubel, Mar 10 2021
  • Mathematica
    Table[n!*SeriesCoefficient[E^(x/(1-x))/(1-x)^5,{x,0,n}],{n,0,20}] (* Vaclav Kotesovec, Oct 11 2012 *)
    With[{nn=20},CoefficientList[Series[Exp[x/(1-x)]/(1-x)^5,{x,0,nn}],x] Range[0,nn]!] (* Harvey P. Dale, Jul 11 2025 *)
  • PARI
    my(x='x+O('x^66)); Vec(serlaplace(exp(x/(1-x))/(1-x)^5)) \\ Joerg Arndt, May 06 2013
    
  • PARI
    a(n) = vecsum(apply(abs,Vec(n!*pollaguerre(n, 4)))); \\ Michel Marcus, Feb 06 2021
    
  • Sage
    [factorial(n)*gen_laguerre(n, 4, -1) for n in (0..30)] # G. C. Greubel, Mar 10 2021

Formula

E.g.f.: exp(x/(1-x))/(1-x)^5.
a(n) = Sum_{m=0..n} n!*binomial(n+4, n-m)/m!.
a(n) = 2*(n+2)*a(n-1) - (n-1)*(n+3)*a(n-2). - Vaclav Kotesovec, Oct 11 2012
a(n) ~ exp(2*sqrt(n)-n-1/2)*n^(n+9/4)/sqrt(2). - Vaclav Kotesovec, Oct 11 2012
a(n) = n!*LaguerreL(n, 4, -1). - G. C. Greubel, Mar 10 2021

A216313 Total number of cycles in all partial permutations of {1,2,...,n}.

Original entry on oeis.org

0, 1, 5, 29, 200, 1609, 14809, 153453, 1767240, 22383681, 309123733, 4621295117, 74331184256, 1279614456041, 23470211031097, 456836915073277, 9403557603534960, 204061142480099649, 4655419598313230277, 111378768040665868093, 2788108620329147151896
Offset: 0

Views

Author

Geoffrey Critzer, Sep 04 2012

Keywords

Crossrefs

Programs

  • Mathematica
    nn=20;t=Sum[n^(n-1)x^n/n!,{n,1,nn}];Range[0,nn]!CoefficientList[ Series[D[Exp[ x/(1-x)]/(1-x)^y,y]/.y->1,{x,0,nn}],x]

Formula

E.g.f.: exp(x/(1-x))*log(1/(1-x))/(1-x).
a(n) = sum(k=0..n, A216294(n,k)*k ).
a(n) = (4*n-3)*a(n-1) - (6*n^2 - 17*n + 13)*a(n-2) + (n-2)^2*(4*n-9)*a(n-3) - (n-3)^3*(n-2)*a(n-4). - Vaclav Kotesovec, Sep 24 2013
a(n) ~ sqrt(2)/4 * n^(n+1/4) * exp(2*sqrt(n)-n-1/2) * (log(n)*(1 + 31/(48*sqrt(n)) + 553/(4608*n)) + 1/sqrt(n) + 43/(48*n)). - Vaclav Kotesovec, Sep 24 2013
Showing 1-5 of 5 results.