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.

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A228912 a(n) = 10^n - 9*9^n + 36*8^n - 84*7^n + 126*6^n - 126*5^n + 84*4^n - 36*3^n + 9*2^n - 1.

Original entry on oeis.org

0, 0, 0, 0, 0, 0, 0, 0, 0, 362880, 19958400, 618710400, 14270256000, 273158645760, 4595022432000, 70309810771200, 1000944296352000, 13467262000832640, 173201547619900800, 2147373231974006400, 25832386565857872000, 303056981918271947520, 3481253462769108364800
Offset: 0

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Author

Keywords

Comments

Calculates the tenth column of coefficients with respect to the derivatives, d^n/dx^n(y), of the logistic equation when written as y = 1/[1+exp(-x)].

Crossrefs

Tenth column of results of A163626.
Essentially 362880*A049435.
Cf. A228910 (with more crossrefs), A228911.

Programs

  • Mathematica
    Table[9!*StirlingS2[n+1, 10], {n, 0, 20}] (* Vaclav Kotesovec, Dec 16 2014 *)
    Table[10^n-9*9^n+36*8^n-84*7^n+126*6^n-126*5^n+84*4^n-36*3^n+9*2^n-1, {n, 0, 20}] (* Vaclav Kotesovec, Dec 16 2014 *)
    CoefficientList[Series[362880*x^9 / ((x-1)*(2*x-1)*(3*x-1)*(4*x-1)*(5*x-1)*(6*x-1)*(7*x-1)*(8*x-1)*(9*x-1)*(10*x-1)), {x, 0, 20}], x] (* Vaclav Kotesovec, Dec 16 2014 after Colin Barker *)
  • PARI
    a(n)=10^n-9*9^n+36*8^n-84*7^n+126*6^n-126*5^n+84*4^n-36*3^n+9*2^n-1

Formula

G.f.: 362880*x^9 / ((x-1)*(2*x-1)*(3*x-1)*(4*x-1)*(5*x-1)*(6*x-1)*(7*x-1)*(8*x-1)*(9*x-1)*(10*x-1)). - Colin Barker, Sep 20 2013
E.g.f.: Sum_{k=1..10} (-1)^(10-k)*binomial(10-1,k-1)*exp(k*x). - Wolfdieter Lang, May 03 2017

Extensions

Offset corrected by Vaclav Kotesovec, Dec 16 2014

A228913 a(n) = 11^n-10*10^n+45*9^n-120*8^n+210*7^n-252*6^n+210*5^n-120*4^n+45*3^n-10*2^n+1.

Original entry on oeis.org

0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3628800, 239500800, 8821612800, 239740300800, 5368729766400, 105006251750400, 1858166876966400, 30449278610150400, 469614684719980800, 6897777008118796800, 97349279409046828800, 1329165939158093836800, 17651395149921751680000
Offset: 0

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Author

Keywords

Comments

Calculates the eleventh column of coefficients with respect to the derivatives, d^n/dx^n(y), of the logistic equation when written as y=1/[1+exp(-x)].

Crossrefs

Eleventh column of results of A163626.
Cf. A228910 (with more cf.s), A228911, A228912.

Programs

  • Mathematica
    Table[10!*StirlingS2[n+1, 11], {n, 0, 20}] (* Vaclav Kotesovec, Dec 16 2014 *)
    CoefficientList[Series[-3628800*x^10 / ((x-1)*(2*x-1)*(3*x-1)*(4*x-1)*(5*x-1)*(6*x-1)*(7*x-1)*(8*x-1)*(9*x-1)*(10*x-1)*(11*x-1)), {x, 0, 20}], x] (* Vaclav Kotesovec, Dec 16 2014 *)
    Table[11^n-10*10^n+45*9^n-120*8^n+210*7^n-252*6^n+210*5^n-120*4^n+45*3^n-10*2^n+1, {n, 0, 20}] (* Vaclav Kotesovec, Dec 16 2014 *)
    LinearRecurrence[{66,-1925,32670,-357423,2637558,-13339535,45995730,-105258076,150917976,-120543840,39916800},{0,0,0,0,0,0,0,0,0,0,3628800},30] (* Harvey P. Dale, Mar 20 2017 *)
  • PARI
    a(n)=11^n-10*10^n+45*9^n-120*8^n+210*7^n-252*6^n+210*5^n-120*4^n+45*3^n-10*2^n+1

Formula

G.f.: -3628800*x^10 / ((x-1)*(2*x-1)*(3*x-1)*(4*x-1)*(5*x-1)*(6*x-1)*(7*x-1)*(8*x-1)*(9*x-1)*(10*x-1)*(11*x-1)). - Colin Barker, Sep 20 2013
E.g.f.: Sum_{k=1..11} (-1)^(11-k)*binomial(11-1,k-1)*exp(k*x). - Wolfdieter Lang, May 03 2017

Extensions

Offset corrected by Vaclav Kotesovec, Dec 16 2014

A051782 Apply the "Stirling-Bernoulli transform" to Catalan numbers.

Original entry on oeis.org

1, 0, 2, -12, 122, -1620, 26882, -536172, 12506762, -334261380, 10075002962, -338180323932, 12512502202202, -505992958647540, 22204726014875042, -1050993549782729292, 53373431773793542442, -2894886293042487680100, 167021024758368026331122
Offset: 0

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Author

N. J. A. Sloane, Dec 09 1999

Keywords

Comments

The "Stirling-Bernoulli transform" maps a sequence b_0, b_1, b_2, ... to a sequence c_0, c_1, c_2, ..., where if B has o.g.f. B(x), c has e.g.f. exp(x)*B(1-exp(x)). More explicitly, c_n = Sum_{m=0..n} (-1)^m*m!*Stirling2(n+1,m+1)*b_m.

Crossrefs

Programs

  • Maple
    a:= n-> add((-1)^k *k! *Stirling2(n+1, k+1)*binomial(2*k, k)/
            (k+1), k=0..n):
    seq(a(n), n=0..20);  # Alois P. Heinz, May 17 2013
  • Mathematica
    a[n_] := Sum[(-1)^k k! StirlingS2[n+1, k+1] CatalanNumber[k], {k, 0, n}];
    Table[a[n], {n, 0, 18}] (* Jean-François Alcover, Apr 06 2016 *)

Formula

a(n) = Sum_{k = 0..n} A163626(n,k)*A000108(k). - Philippe Deléham, May 25 2015

A094485 T(n, k) = Stirling1(n+1, k) - Stirling1(n, k-1), for 1 <= k <= n. Triangle read by rows.

Original entry on oeis.org

-1, 2, -2, -6, 9, -3, 24, -44, 24, -4, -120, 250, -175, 50, -5, 720, -1644, 1350, -510, 90, -6, -5040, 12348, -11368, 5145, -1225, 147, -7, 40320, -104544, 105056, -54152, 15680, -2576, 224, -8, -362880, 986256, -1063116, 605556, -202041, 40824, -4914, 324, -9, 3628800, -10265760, 11727000, -7236800
Offset: 1

Views

Author

Vladeta Jovovic, Jun 05 2004

Keywords

Examples

			Triangle starts:
[n\k    1        2       3      4      5      6     7  8]
[1]    -1;
[2]     2,      -2;
[3]    -6,       9,     -3;
[4]    24,     -44,     24,     -4;
[5]  -120,     250,   -175,     50,    -5;
[6]   720,   -1644,   1350,   -510,    90,    -6;
[7] -5040,   12348, -11368,   5145, -1225,   147,   -7;
[8] 40320, -104544, 105056, -54152, 15680, -2576,  224,  -8;
		

Crossrefs

Programs

  • Maple
    T := (n, k) -> Stirling1(n+1, k) - Stirling1(n, k-1);
    seq(seq(T(n, k), k=1..n), n=1..9); # Peter Luschny, May 26 2020
  • Mathematica
    Table[StirlingS1[n+1,k]-StirlingS1[n,k-1],{n,10},{k,n}]//Flatten (* Harvey P. Dale, Jul 25 2024 *)

Formula

E.g.f.: -x*y*(1+y)^(x-1). [T(n,k) = n!*[x^k]([y^n] -x*y*(y+1)^(x-1)).]
The matrix inverse of the Worpitzky triangle. More precisely:
T(n, k) = -n!*InvW(n, k) where InvW is the matrix inverse of A028246. - Peter Luschny, May 26 2020

Extensions

Offset of k shifted and edited by Peter Luschny, May 26 2020

A142071 Expansion of the exponential generating function 1 - log(1 - x*(exp(z) - 1)), triangle read by rows, T(n,k) for n >= 0 and 0 <= k <= n.

Original entry on oeis.org

1, 0, 1, 0, 1, 1, 0, 1, 3, 2, 0, 1, 7, 12, 6, 0, 1, 15, 50, 60, 24, 0, 1, 31, 180, 390, 360, 120, 0, 1, 63, 602, 2100, 3360, 2520, 720, 0, 1, 127, 1932, 10206, 25200, 31920, 20160, 5040, 0, 1, 255, 6050, 46620, 166824, 317520, 332640, 181440, 40320, 0, 1, 511, 18660
Offset: 0

Views

Author

Roger L. Bagula and Gary W. Adamson, Sep 15 2008

Keywords

Comments

Row n gives the coefficients which express the sums of the n-th powers of the integers as a linear combination of binomial coefficients, thus:
Sum_{k=1..r} k^n = A103438(n+r,r) = Sum_{k=0..n} T(n+1,k) * C(r,k),
where, by convention, C(r,k) = 0 whenever r < k. - Robert B Fowler, Jan 16 2023

Examples

			Triangle begins:
  1;
  0, 1;
  0, 1,   1;
  0, 1,   3,    2;
  0, 1,   7,   12,     6;
  0, 1,  15,   50,    60,    24;
  0, 1,  31,  180,   390,   360,   120;
  0, 1,  63,  602,  2100,  3360,  2520,   720;
  0, 1, 127, 1932, 10206, 25200, 31920, 20160, 5040;
  ...
		

Crossrefs

Column k = 0 is A000007.
Cf. A028246, A163626, A000629 (row sums).
Cf. A103438, A007318 (binomial coefficients).

Programs

  • Maple
    CL := (f, x) -> PolynomialTools:-CoefficientList(f, x):
    A142071row := proc(n) 1 - log(1 - x*(exp(z) - 1)):
    series(%, z, 12): CL(n!*coeff(%, z, n), x) end:
    for n from 0 by 1 to 7 do A142071row(n) od;
    # Alternative:
    A142071Row := proc(n) if n=0 then [1] else
    CL(convert(series(polylog(-n+1, z/(1+z)), z, n*2), polynom), z) fi end:
    seq(A142071Row(n), n=0..6); # Peter Luschny, Sep 06 2018
  • Mathematica
    T[n_, k_] := If[k==0, Floor[1/(n + 1)], (k - 1)!*StirlingS2[n, k]]; Flatten[Table[T[n, k], {n, 0, 10}, {k, 0, n}]] (* Detlef Meya, Jan 06 2024 *)

Formula

Row n gives the coefficients of the polynomial defined by p(x, 0) = 1 and for n > 0 p(x, n) = Sum_{k >= 0} k^(n-1)*(x/(1 + x))^k = PolyLog(-n+1, x/(1+x)).
T(n, k) = (k - 1)! * Stirling2(n, k) for k > 0. - Detlef Meya, Jan 06 2024

Extensions

Edited, T(0,0) = 1 prepended and new name by Peter Luschny, Sep 06 2018

A260196 1, -3, followed by -1's.

Original entry on oeis.org

1, -3, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1
Offset: 0

Views

Author

Paul Curtz, Jul 19 2015

Keywords

Comments

1/(n+1) is the inverse Akiyama-Tanigawa transform of A164555(n)/A027642(n).
For more on the Akiyama-Tanigawa transform, see Links (correction: page 7 read here A164555 instead of A027641) and A177427.
Here:
1, -3, -1, -1, -1, -1, ...
4, -4, 0, 0, 0, 0, ...
8, -8, 0, 0, 0, 0, ...
16, -16, 0, 0, 0, 0, ...
etc.
Other process, using signed A130534(n), different of A008275(n):
1, 1/1, 1,
1, 4, ( 1, -1)/1, -3,
1, 4, 8, ( 2, -3, 1)/2, -1,
1, 4, 8, 16, * ( 6, -11, 6, -1)/6, = -1,
1, 4, 8, 16, 32, ( 24, -50, 35, -10, 1)/24, -1,
1, 4, 8, 16, 32, 64, (120, -274, 225, -85, 15, -1)/120, -1,
etc. etc. etc.
Via the modified Stirling numbers of the first kind, the second triangle, Iw(n), is the inverse of Worpitzky transform A163626(n).
a(n) is the third sequence of a family beginning with
1, 1, 1, 1, 1, 1, 1, 1, ... = A000012(n)
1, 0, 0, 0, 0, 0, 0, 0, 0, ... = A000007(n)
1, -3, -1, -1, -1, -1, -1, -1, -1, -1, ... .
A000012(n) is the inverse Akiyama-Tanigawa transform of A000007(n), with or without its second term.
A000007(n) is the inverse Akiyama-Tanigawa transform of A000012(n), with or without its second term.
a(n) is the inverse Akiyama-Tanigawa transform of 2^n omitting the second term i.e. 2.

Crossrefs

Programs

  • PARI
    first(m)=vector(m,i,i--;if(i>1,-1,if(i==0,1,if(i==1,-3)))) \\ Anders Hellström, Aug 28 2015
    
  • PARI
    Vec(-(2*x^2-4*x+1)/(x-1) + O(x^100)) \\ Colin Barker, Sep 11 2015

Formula

Inverse Akiyama-Tanigawa transform of A151821(n).
From Colin Barker, Sep 11 2015: (Start)
a(n) = -1 for n>1.
a(n) = a(n-1) for n>2.
G.f.: -(2*x^2-4*x+1) / (x-1).
(End)

A344920 The Worpitzky transform of the squares.

Original entry on oeis.org

0, -1, 5, -13, 29, -61, 125, -253, 509, -1021, 2045, -4093, 8189, -16381, 32765, -65533, 131069, -262141, 524285, -1048573, 2097149, -4194301, 8388605, -16777213, 33554429, -67108861, 134217725, -268435453, 536870909, -1073741821, 2147483645, -4294967293
Offset: 0

Views

Author

Peter Luschny, Jun 24 2021

Keywords

Comments

The Worpitzky transform maps a sequence A to a sequence B, where B(n) = Sum_{k=0..n} A163626(n, k)*A(k). (If A(n) = 1/(n + 1) then B(n) are the Bernoulli numbers (with B(1) = 1/2.))
Also row 2 in A371761. Can be generated by the signed Akiyama-Tanigawa algorithm for powers (see the Python script). - Peter Luschny, Apr 12 2024

Crossrefs

Up to shift and sign: even bisection A267921, odd bisection A141725.

Programs

  • Maple
    gf := (exp(x) - 1)*(exp(x) - 2)*exp(-2*x): ser := series(gf, x, 36):
    seq(n!*coeff(ser, x, n), n = 0..31);
  • Mathematica
    W[n_, k_] := (-1)^k k! StirlingS2[n + 1, k + 1];
    WT[a_, len_] := Table[Sum[W[n, k] a[k], {k, 0, n}], {n, 0, len-1}];
    WT[#^2 &, 32] (* The Worpitzky transform applied to the squares. *)
  • Python
    # Using the Akiyama-Tanigawa algorithm for powers from A371761.
    print([(-1)**n * v for (n, v) in enumerate(ATPowList(2, 32))])
    # Peter Luschny, Apr 12 2024

Formula

a(n) = n! * [x^n] (exp(x) - 1)*(exp(x) - 2)*exp(-2*x).
a(n) = (-1)^(n + 1)*(3 - 2^(n + 1)) for n >= 1. - Hugo Pfoertner, Jun 24 2021
a(n) = [x^n] x*(2*x - 1)/(2*x^2 + 3*x + 1). - Stefano Spezia, Jun 24 2021

A258369 Stirling-Bernoulli transform of A027656.

Original entry on oeis.org

1, 1, 5, 25, 173, 1441, 14165, 160105, 2044733, 29105521, 456781925, 7834208185, 145760370893, 2923764916801, 62891469229685, 1444055265984265, 35250519098274653, 911569049328779281, 24893164161460525445, 715822742720760256345, 21620050147748210572013
Offset: 0

Views

Author

Philippe Deléham, May 28 2015

Keywords

Comments

Also called Akiyama-Tanigawa transform of A027656.

Examples

			a(0) = 1*1 = 1.
a(1) = 1*1 = 1.
a(2) = 1*1 + 2*2 = 5.
a(3) = 1*1 + 12*2 = 25.
a(4) = 1*1 + 50*2 + 24*3 = 173.
		

Crossrefs

Formula

a(n) = Sum_{k = 0..n} A163626(n,k)*A027656(k).
a(n) = Sum_{k>=0} A249163(n,k) * (k+1).
E.g.f.: 1/(exp(x)*(2 - exp(x))^2).
a(n) ~ n! * n / (8 * (log(2))^(n+2)). - Vaclav Kotesovec, Jul 01 2018

A318259 Generalized Worpitzky numbers W_{m}(n,k) for m = 2, n >= 0 and 0 <= k <= n, triangle read by rows.

Original entry on oeis.org

1, -1, 1, 5, -11, 6, -61, 211, -240, 90, 1385, -6551, 11466, -8820, 2520, -50521, 303271, -719580, 844830, -491400, 113400, 2702765, -19665491, 58998126, -93511440, 82661040, -38669400, 7484400, -199360981, 1704396331, -6187282920, 12372329970, -14727913200, 10443232800, -4086482400, 681080400
Offset: 0

Views

Author

Peter Luschny, Sep 06 2018

Keywords

Comments

The triangle can be seen as a member of a family of generalized Worpitzky numbers A028246. See the cross-references for some other members.
The unsigned numbers have row sums A210657 which points to an interpretation of the unsigned numbers as a refinement of marked Schröder paths (see Josuat-Vergès and Kim).

Examples

			[0] [      1]
[1] [     -1,         1]
[2] [      5,       -11,        6]
[3] [    -61,       211,     -240,        90]
[4] [   1385,     -6551,    11466,     -8820,     2520]
[5] [ -50521,    303271,  -719580,    844830,  -491400,    113400]
[6] [2702765, -19665491, 58998126, -93511440, 82661040, -38669400, 7484400]
		

Crossrefs

Row sums are A000007, alternating row sums are A210657.
Cf. T(n,n) = A000680, T(n, 0) = A028296(n) (Gudermannian), A000364 (Euler secant), A241171 (Joffe's differences), A028246 (Worpitzky).
Cf. A167374 (m=0), A028246 & A163626 (m=1), this seq (m=2), A318260 (m=3).

Programs

  • Maple
    Joffe := proc(n, k) option remember; if k > n then 0 elif k = 0 then k^n else
    k*(2*k-1)*Joffe(n-1, k-1)+k^2*Joffe(n-1, k) fi end:
    T := (n, k) -> add((-1)^(k-j)*binomial(n-j, n-k)*add((-1)^i*Joffe(n,i)*
    binomial(n-i, j), i=0..n), j=0..k):
    seq(seq(T(n, k), k=0..n), n=0..6);
  • Mathematica
    Joffe[0, 0] = 1; Joffe[n_, k_] := Joffe[n, k] = If[k>n, 0, If[k == 0,k^n, k*(2*k-1)*Joffe[n-1, k-1] + k^2*Joffe[n-1, k]]];
    T[n_, k_] := Sum[(-1)^(k-j)*Binomial[n-j, n-k]*Sum[(-1)^i*Joffe[n, i]* Binomial[n-i, j], {i, 0, n}], {j, 0, k}];
    Table[T[n, k], {n, 0, 7}, {k, 0, n}] // Flatten (* Jean-François Alcover, Feb 18 2019, from Maple *)
  • Sage
    def EW(m, n):
        @cached_function
        def S(m, n):
            R. = ZZ[]
            if n == 0: return R(1)
            return R(sum(binomial(m*n, m*k)*S(m, n-k)*x for k in (1..n)))
        s = S(m, n).list()
        c = lambda k: sum((-1)^(k-j)*binomial(n-j,n-k)*
            sum((-1)^i*s[i]*binomial(n-i,j) for i in (0..n)) for j in (0..k))
        return [c(k) for k in (0..n)]
    def A318259row(n): return EW(2, n)
    flatten([A318259row(n) for n in (0..6)])

Formula

Let S(n, k) denote Joffe's central differences of zero (A241171) extended to the case n = 0 and k = 0 by prepending a column 1, 0, 0, 0,... to the triangle, then:
T(n,k) = Sum_{j=0..k}((-1)^(k-j)*C(n-j,n-k)*Sum_{i=0..n}((-1)^i*S(n,i)*C(n-i,j))).

A318260 Generalized Worpitzky numbers W_{m}(n,k) for m = 3, n >= 0 and 0 <= k <= n, triangle read by rows.

Original entry on oeis.org

1, -1, 1, 19, -39, 20, -1513, 4705, -4872, 1680, 315523, -1314807, 2052644, -1422960, 369600, -136085041, 710968441, -1484552160, 1548707160, -807206400, 168168000, 105261234643, -661231439271, 1729495989332, -2410936679424, 1889230062720, -789044256000, 137225088000
Offset: 0

Views

Author

Peter Luschny, Sep 06 2018

Keywords

Comments

The triangle can be seen as a member of a family of generalized Worpitzky numbers A028246. See A318259 and the cross-references for some other members.

Examples

			[0] [         1]
[1] [        -1,         1]
[2] [        19,       -39,          20]
[3] [     -1513,      4705,       -4872,       1680]
[4] [    315523,  -1314807,     2052644,   -1422960,     369600]
[5] [-136085041, 710968441, -1484552160, 1548707160, -807206400, 168168000]
		

Crossrefs

Cf. T(n,0) ~ A002115(n) (signed), T(n,n) = A014606.
Cf. A167374 (m=0), A028246 & A163626 (m=1), A318259 (m=2), this seq (m=3).

Programs

  • Sage
    # uses[EW from A318259]
    def A318260row(n): return EW(3, n)
    print(flatten([A318260row(n) for n in (0..6)]))

Formula

Let P(m,n) = Sum_{k=1..n} binomial(m*n, m*k)*P(m, n-k)*x with P(m,0) = 1
and S(n,k) = [x^k]P(3,n), then T(n,k) = Sum_{j=0..k}((-1)^(k-j)*binomial(n-j, n-k)* Sum_{i=0..n}((-1)^i*S(n,i)*binomial(n-i,j))).
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