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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A265604 Triangle read by rows: The inverse Bell transform of the quartic factorial numbers (A007696).

Original entry on oeis.org

1, 0, 1, 0, 1, 1, 0, -2, 3, 1, 0, 10, -5, 6, 1, 0, -80, 30, -5, 10, 1, 0, 880, -290, 45, 5, 15, 1, 0, -12320, 3780, -560, 35, 35, 21, 1, 0, 209440, -61460, 8820, -735, 0, 98, 28, 1, 0, -4188800, 1192800, -167300, 14700, -735, 0, 210, 36, 1
Offset: 0

Views

Author

Peter Luschny, Dec 30 2015

Keywords

Examples

			[ 1]
[ 0,      1]
[ 0,      1,      1]
[ 0,     -2,      3,      1]
[ 0,     10,     -5,      6,      1]
[ 0,    -80,     30,     -5,     10,      1]
[ 0,    880,   -290,     45,      5,     15,      1]
		

Crossrefs

Inverse Bell transforms of other multifactorials are: A048993, A049404, A049410, A075497, A075499, A075498, A119275, A122848, A265605.

Programs

  • Sage
    # uses[bell_transform from A264428]
    def inverse_bell_matrix(generator, dim):
        G = [generator(k) for k in srange(dim)]
        row = lambda n: bell_transform(n, G)
        M = matrix(ZZ, [row(n)+[0]*(dim-n-1) for n in srange(dim)]).inverse()
        return matrix(ZZ, dim, lambda n,k: (-1)^(n-k)*M[n,k])
    multifact_4_1 = lambda n: prod(4*k + 1 for k in (0..n-1))
    print(inverse_bell_matrix(multifact_4_1, 8))

A265605 Triangle read by rows: The inverse Bell transform of the triple factorial numbers (A007559).

Original entry on oeis.org

1, 0, 1, 0, 1, 1, 0, -1, 3, 1, 0, 3, -1, 6, 1, 0, -15, 5, 5, 10, 1, 0, 105, -35, 0, 25, 15, 1, 0, -945, 315, -35, 0, 70, 21, 1, 0, 10395, -3465, 490, -35, 70, 154, 28, 1, 0, -135135, 45045, -6895, 630, -105, 378, 294, 36, 1
Offset: 0

Views

Author

Peter Luschny, Dec 30 2015

Keywords

Examples

			[ 1]
[ 0,    1]
[ 0,    1,    1]
[ 0,   -1,    3,    1]
[ 0,    3,   -1,    6,    1]
[ 0,  -15,    5,    5,   10,    1]
[ 0,  105,  -35,    0,   25,   15,    1]
[ 0, -945,  315,  -35,    0,   70,   21,    1]
		

Crossrefs

Inverse Bell transforms of other multifactorials are: A048993, A049404, A049410, A075497, A075499, A075498, A119275, A122848, A265604.

Programs

  • Sage
    # uses[bell_transform from A264428]
    def inverse_bell_matrix(generator, dim):
        G = [generator(k) for k in srange(dim)]
        row = lambda n: bell_transform(n, G)
        M = matrix(ZZ, [row(n)+[0]*(dim-n-1) for n in srange(dim)]).inverse()
        return matrix(ZZ, dim, lambda n,k: (-1)^(n-k)*M[n,k])
    multifact_3_1 = lambda n: prod(3*k + 1 for k in (0..n-1))
    print(inverse_bell_matrix(multifact_3_1, 8))

A028085 Expansion of 1/((1-3x)(1-6x)(1-9x)(1-12x)).

Original entry on oeis.org

1, 30, 585, 9450, 137781, 1888110, 24862545, 318755250, 4012058061, 49847787990, 613622150505, 7503229474650, 91300979746341, 1106997911204670, 13386607046238465, 161563913916523650
Offset: 0

Views

Author

Keywords

Crossrefs

Fourth column of triangle A075498.

Programs

  • Mathematica
    CoefficientList[Series[1/((1-3x)(1-6x)(1-9x)(1-12x)),{x,0,30}],x] (* or *) LinearRecurrence[{30,-315,1350,-1944},{1,30,585,9450},30] (* Harvey P. Dale, Feb 06 2015 *)
  • PARI
    Vec(1/((1-3*x)*(1-6*x)*(1-9*x)*(1-12*x))+O(x^99)) \\ Charles R Greathouse IV, Sep 26 2012

Formula

a(n) = (3^n)*Stirling2(n+4, 4), n >= 0, with Stirling2(n, m) = A008277(n, m).
a(n) = Sum_{m=0..3} (A075513(4, m)*((m+1)*3)^n)/3!.
G.f.: 1/Product_{k=1..4} (1-3*k*x).
E.g.f.: (d^4/dx^4)((((exp(3*x)-1)/3)^4)/4!) = Sum_{m=0..3} (A075513(4, m)*exp(3*(m+1)*x))/3!.
a(n) = (12^(n+3) - 3*9^(n+3) + 3*6^(n+3) - 3^(n+3))/162. - Yahia Kahloune, Jun 10 2013
a(0)=1, a(1)=30, a(2)=585, a(3)=9450, a(n) = 30*a(n-1) - 315*a(n-2) + 1350*a(n-3) - 1944*a(n-4). - Harvey P. Dale, Feb 06 2015
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