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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A156584 Triangle T(n,k) = SF(n+1)/(SF(n-k+1)*SF(k+1)) where SF(n) is the superfactorial A000178(n), read by rows.

Original entry on oeis.org

1, 1, 1, 1, 3, 1, 1, 12, 12, 1, 1, 60, 240, 60, 1, 1, 360, 7200, 7200, 360, 1, 1, 2520, 302400, 1512000, 302400, 2520, 1, 1, 20160, 16934400, 508032000, 508032000, 16934400, 20160, 1, 1, 181440, 1219276800, 256048128000, 1536288768000, 256048128000, 1219276800, 181440, 1
Offset: 0

Views

Author

Roger L. Bagula, Feb 10 2009

Keywords

Examples

			Triangle begins as:
  1;
  1,     1;
  1,     3,        1;
  1,    12,       12,         1;
  1,    60,      240,        60,         1;
  1,   360,     7200,      7200,       360,        1;
  1,  2520,   302400,   1512000,    302400,     2520,     1;
  1, 20160, 16934400, 508032000, 508032000, 16934400, 20160, 1;
		

Crossrefs

Cf. A007318 (m=0), this sequence (m=1), A156764 (m=3).
Cf. A009963.

Programs

  • Maple
    SF := n -> mul(j!, j=0..n): T := (n,k) -> SF(n-1)/(SF(n-k)*SF(k)):
    seq(print(seq(T(n,k),k=1..n-1)),n=0..9); # Peter Luschny, Jan 24 2015
  • Mathematica
    (* First program *)
    b[n_, k_]:= If[k==0, n!, Product[Sum[(-1)^(i+j)*(j+1)*StirlingS1[j-1, i]*(k+1)^i, {i, 0, j-1}], {j, 1, n}]];
    T[n_, k_, m_] = If[n==0, 1, b[n, m]/(b[k, m]*b[n-k, m])];
    Table[T[n, k, 1], {n,0,12}, {k,0,n}]//Flatten (* modified by G. C. Greubel, Jun 20 2021 *)
    (* Second program *)
    f[n_, k_]:= If[k==0, n!, (-1)^n*(n+1)!*BarnesG[n+k+1]/(Gamma[k+1]^n*BarnesG[k+1])];
    T[n_, k_, m_]:= If[n==0, 1, f[n,m]/(f[k,m]*f[n-k,m])];
    Table[T[n,k,1], {n,0,12}, {k,0,n}]//Flatten (* G. C. Greubel, Jun 20 2021 *)
  • Sage
    def f(n,k): return factorial(n) if (k==0) else (-1)^n*factorial(n+1)*product( rising_factorial(k+1, j) for j in (0..n-1) )
    def T(n,k,m): return 1 if (n==0) else f(n,m)/(f(k,m)*f(n-k,m))
    flatten([[T(n,k,1) for k in (0..n)] for n in (0..12)]) # G. C. Greubel, Jun 21 2021

Formula

From G. C. Greubel, Jun 21 2021: (Start)
T(n, k) = BarnesG(n+3)/(BarnesG(k+3)*BarnesG(n-k+3)).
T(n, k, m) = f(n, m)/(f(k, m)*f(n-k, m)), with T(0, k, m) = 1, f(n, k) = (-1)^n*(n + 1)!*BarnesG(n+k+1)/(Gamma(k+1)^n*BarnesG(k+1)), f(n, 0) = n!, and m = 1. (End)

Extensions

New name and editing, Peter Luschny, Jan 24 2015

A193521 G.f.: A(x) = ( Sum_{n>=0} x^n/sf(n) )^3 where A(x) = Sum_{n>=0} a(n)*x^n/sf(n), and sf(n) = Product_{k=0..n} k! is the superfactorial of n (A000178).

Original entry on oeis.org

1, 3, 9, 51, 795, 43923, 10372323, 11996843043, 75315947454723, 2788806652875290883, 654625444656522114316803, 1045012738906587147509753740803, 12046169853230117709495421609499289603, 1053916215003128938522329980606467994425804803
Offset: 0

Views

Author

Paul D. Hanna, Jul 29 2011

Keywords

Examples

			Let F(x) = 1 + x + x^2/(1!*2!) + x^3/(1!*2!*3!) + x^4/(1!*2!*3!*4!) + ... + x^n/sf(n) + ...
then F(x)^3 = 1 + 3*x + 9*x^2/(1!*2!) + 51*x^3/(1!*2!*3!) + 795*x^4/(1!*2!*3!*4!) + 43923*x^5/(1!*2!*3!*4!*5!) + ... + a(n)*x^n/sf(n) + ...
		

Crossrefs

Programs

  • Magma
    A193521:= func< n | (&+[ A009963(n,k)*A193520(k): k in [0..n]]) >;
    [A193521(n): n in [0..20]]; // G. C. Greubel, Jan 05 2022
    
  • Mathematica
    a[n_]:= a[n]= Sum[BarnesG[n+2]/(BarnesG[j+2]*BarnesG[k-j+2]*BarnesG[n-k+2]), {k,0,n}, {j,0,k}];
    Table[a[n], {n, 0, 20}] (* G. C. Greubel, Jan 05 2022 *)
  • PARI
    {a(n) = prod(k=1,n,k!)*polcoeff((sum(m=0, n+1, x^m/prod(k=0, m, k!) + x*O(x^n))^3), n)}
    
  • Sage
    @CachedFunction
    def A009963(n,k): return product(factorial(n-j+1)/factorial(j) for j in (1..k))
    def A193521(n): return sum(sum(A009963(n,k)*A009963(k,j) for j in (0..k)) for k in (0..n))
    [A193521(n) for n in (0..20)] # G. C. Greubel, Jan 05 2022

Formula

From G. C. Greubel, Jan 05 2022: (Start)
a(n) = Sum_{k=0..n} Sum_{j=0..k} BarnesG(n+2)/(BarnesG(j+2)*BarnesG(k-j+2 )*BarnesG(n-k+2)).
a(n) = Sum_{k=0..n} A009963(n, k) * Sum_{j=0..k} A009963(k, j).
a(n) = Sum_{j=0..n} A009963(n, j)*A193520(j). (End)
a(n) ~ c(n) * A^2 * 3^(5/4 + n + n^2/6) * n^(-5/6 + n^2/3) / (2*Pi * exp(1/6 + n^2/2)), where c(n) = 1 if mod(n,3) = 0 and c(n) = 3^(4/3) / n^(1/3) if mod(n,3) = 1 or if mod(n,3) = 2, A = A074962 is the Glaisher-Kinkelin constant. - Vaclav Kotesovec, Aug 29 2023

A156586 A new q-combination type general triangle sequence based on Stirling first polynomials: here q=4: m=3: t(n,k)=If[m == 0, n!, Product[Sum[(-1)^(i + k)*StirlingS1[k - 1, i]*(m + 1)^i, {i, 0, k - 1}], {k, 1, n}]]; b(n,k,m)=If[n == 0, 1, t[n, m]/(t[k, m]*t[n - k, m])].

Original entry on oeis.org

1, 1, 1, 1, 4, 1, 1, 20, 20, 1, 1, 120, 600, 120, 1, 1, 840, 25200, 25200, 840, 1, 1, 6720, 1411200, 8467200, 1411200, 6720, 1, 1, 60480, 101606400, 4267468800, 4267468800, 101606400, 60480, 1, 1, 604800, 9144576000, 3072577536000, 21508042752000
Offset: 0

Views

Author

Roger L. Bagula, Feb 10 2009

Keywords

Comments

Row sums are:
{1, 2, 6, 42, 842, 52082, 11303042, 8738271362, 27671488185602,
346773112532985602, 20244862147392528307202,...}.
The q=2 sequence is A009963.

Examples

			{1},
{1, 1},
{1, 4, 1},
{1, 20, 20, 1},
{1, 120, 600, 120, 1},
{1, 840, 25200, 25200, 840, 1},
{1, 6720, 1411200, 8467200, 1411200, 6720, 1},
{1, 60480, 101606400, 4267468800, 4267468800, 101606400, 60480, 1},
{1, 604800, 9144576000, 3072577536000, 21508042752000, 3072577536000, 9144576000, 604800, 1},
{1, 6652800, 1005903360000, 3041851760640000, 170343698595840000, 170343698595840000, 3041851760640000, 1005903360000, 6652800, 1},
{1, 79833600, 132779243520000, 4015244324044800000, 2023683139318579200000, 16189465114548633600000, 2023683139318579200000, 4015244324044800000, 132779243520000, 79833600, 1}
		

Crossrefs

Programs

  • Mathematica
    Clear[t, n, m, i, k, a, b];
    t[n_, m_] = If[m == 0, n!, Product[Sum[(-1)^(i + k)*StirlingS1[k - 1, i]*(m + 1)^i, {i, 0, k - 1}], {k, 1, n}]];
    b[n_, k_, m_] = If[n == 0, 1, t[n, m]/(t[k, m]*t[n - k, m])];
    Table[Flatten[Table[Table[b[n, k, m], {k, 0, n}], {n, 0, 10}]], {m, 0, 15}]

Formula

q=4: m=3:
t(n,k)=If[m == 0, n!, Product[Sum[(-1)^(i + k)*StirlingS1[k - 1, i]*(m + 1)^i, {i, 0, k - 1}], {k, 1, n}]];
b(n,k,m)=If[n == 0, 1, t[n, m]/(t[k, m]*t[n - k, m])].

A156587 A new q-combination type general triangle sequence based on Stirling first polynomials: here q=5: m=4: t(n,k)=If[m == 0, n!, Product[Sum[(-1)^(i + k)*StirlingS1[k - 1, i]*(m + 1)^i, {i, 0, k - 1}], {k, 1, n}]]; b(n,k,m)=If[n == 0, 1, t[n, m]/(t[k, m]*t[n - k, m])].

Original entry on oeis.org

1, 1, 1, 1, 5, 1, 1, 30, 30, 1, 1, 210, 1260, 210, 1, 1, 1680, 70560, 70560, 1680, 1, 1, 15120, 5080320, 35562240, 5080320, 15120, 1, 1, 151200, 457228800, 25604812800, 25604812800, 457228800, 151200, 1, 1, 1663200, 50295168000, 25348764672000
Offset: 0

Views

Author

Roger L. Bagula, Feb 10 2009

Keywords

Comments

Row sums are:
{1, 2, 7, 62, 1682, 144482, 45753122, 52124385602, 253588240382402,
4885227205552108802, 454865349223042267910402,...}.
The q=2 sequence is A009963.

Examples

			{1},
{1, 1},
{1, 5, 1},
{1, 30, 30, 1},
{1, 210, 1260, 210, 1},
{1, 1680, 70560, 70560, 1680, 1},
{1, 15120, 5080320, 35562240, 5080320, 15120, 1},
{1, 151200, 457228800, 25604812800, 25604812800, 457228800, 151200, 1},
{1, 1663200, 50295168000, 25348764672000, 202790117376000, 25348764672000, 50295168000, 1663200, 1},
{1, 19958400, 6638962176000, 33460369367040000, 2409146594426880000, 2409146594426880000, 33460369367040000, 6638962176000, 19958400, 1},
{1, 259459200, 1035678099456000, 57417993833840640000, 41340955560365260800000, 372068600043287347200000, 41340955560365260800000, 57417993833840640000, 1035678099456000, 259459200, 1}
		

Crossrefs

Programs

  • Mathematica
    Clear[t, n, m, i, k, a, b];
    t[n_, m_] = If[m == 0, n!, Product[Sum[(-1)^(i + k)*StirlingS1[k - 1, i]*(m + 1)^i, {i, 0, k - 1}], {k, 1, n}]];
    b[n_, k_, m_] = If[n == 0, 1, t[n, m]/(t[k, m]*t[n - k, m])];
    Table[Flatten[Table[Table[b[n, k, m], {k, 0, n}], {n, 0, 10}]], {m, 0, 15}]

Formula

q=5: m=4:
t(n,k)=If[m == 0, n!, Product[Sum[(-1)^(i + k)*StirlingS1[k - 1, i]*(m + 1)^i, {i, 0, k - 1}], {k, 1, n}]];
b(n,k,m)=If[n == 0, 1, t[n, m]/(t[k, m]*t[n - k, m])].

A156588 A triangle of q factorial type based on Stirling first polynomials: t(n,k)=If[m == 0, n!, Product[Sum[(-1)^(i + k)*StirlingS1[k - 1, i]*(m + 1)^i, {i, 0, k - 1}], {k, 1, n}]].

Original entry on oeis.org

1, 1, 1, 1, -1, 2, 1, -1, 2, 6, 1, -1, 3, -12, 24, 1, -1, 4, -36, 288, 120, 1, -1, 5, -80, 2160, -34560, 720, 1, -1, 6, -150, 9600, -777600, 24883200, 5040, 1, -1, 7, -252, 31500, -8064000, 1959552000, -125411328000, 40320, 1, -1, 8, -392, 84672, -52920000
Offset: 0

Views

Author

Roger L. Bagula, Feb 10 2009

Keywords

Comments

Row sums are:
{1, 2, 2, 8, 15, 376, -31755, 24120096, -123459768425, 5017134314247168,
-1827769039991244222327,...}.

Examples

			{1},
{1, 1},
{1, -1, 2},
{1, -1, 2, 6},
{1, -1, 3, -12, 24},
{1, -1, 4, -36, 288, 120},
{1, -1, 5, -80, 2160, -34560, 720},
{1, -1, 6, -150, 9600, -777600, 24883200, 5040},
{1, -1, 7, -252, 31500, -8064000, 1959552000, -125411328000, 40320},
{1, -1, 8, -392, 84672, -52920000, 54190080000, -39504568320000, 5056584744960000, 362880},
{1, -1, 9, -576, 197568, -256048128, 800150400000, -3277416038400000, 7167708875980800000, -1834933472251084800000, 3628800}
		

Crossrefs

Programs

  • Mathematica
    Clear[t, n, m, i, k, a, b];
    t[n_, m_] = If[m == 0, n!, Product[Sum[(-1)^(i + k)*StirlingS1[k - 1, i]*(m + 1)^i, {i, 0, k - 1}], {k, 1, n}]];
    a = Table[Table[t[n, m], {n, 0, 10}], {m, 0, 10}];
    b = Table[Table[a[[m, n - m + 1]], {m, n, 1, -1}], {n, 1, Length[a]}];
    Flatten[%]

Formula

t(n,k)=If[m == 0, n!, Product[Sum[(-1)^(i + k)*StirlingS1[k - 1, i]*(m + 1)^i, {i, 0, k - 1}], {k, 1, n}]];
out_(n,k)=Antidiagonal(t(n,k)).

A335997 Triangle read by rows: T(n,k) = Product_{i=n-k+1..n} i! for 0 <= k <= n.

Original entry on oeis.org

1, 1, 1, 1, 2, 2, 1, 6, 12, 12, 1, 24, 144, 288, 288, 1, 120, 2880, 17280, 34560, 34560, 1, 720, 86400, 2073600, 12441600, 24883200, 24883200, 1, 5040, 3628800, 435456000, 10450944000, 62705664000, 125411328000, 125411328000
Offset: 0

Views

Author

Werner Schulte, Jul 08 2020

Keywords

Comments

Based on some integer sequence a(n), n>0, define triangular arrays A(a;n,k) by recurrence: A(a;0,0) = 1, and A(a;i,j) = 0 if j<0 or j>i, and A(a;n,k) = n! / (n-k)! * A(a;n-1,k) + a(n) * A(a;n-1,k-1) for 0<=k<=n. Then, Product_{i=1..n} (1 + (a(i) / i!) * x) = Sum_{k=0..n} A(a;n,k) / T(n,k) * x^k for n>=0 with empty product 1 (case n=0).
For the row reversed triangle R(n,k) = Product_{i=k+1..n} i! with empty product 1 (case k=n) the terms of the matrix inverse M are given by M(n,n) = 1 for n >= 0 and M(n,n-1) = -n! for n > 0 otherwise 0. - Werner Schulte, Oct 25 2022

Examples

			The triangle starts:
n\k :  0     1      2        3         4         5         6
============================================================
  0 :  1
  1 :  1     1
  2 :  1     2      2
  3 :  1     6     12       12
  4 :  1    24    144      288       288
  5 :  1   120   2880    17280     34560     34560
  6 :  1   720  86400  2073600  12441600  24883200  24883200
  etc.
		

Crossrefs

Cf. A000012 (col_0), A000142 (col_1), A010790 (col_2), A176037 (col_3), A000178 (main diagonal and first subdiagonal).
Row sums equal A051399(n+1).

Programs

  • Mathematica
    T[n_, k_] := Product[i!, {i, n - k + 1, n}]; Table[T[n, k], {n, 0, 7}, {k, 0, n}] // Flatten (* Amiram Eldar, Jul 08 2020 *)

Formula

T(n,k) = T(n,1) * T(n-1,k-1) for 0 < k <= n.
T(2*n,n) = A093002(n+1) for n >= 0.
T(n,k)/T(k,k) = A009963(n,k) for 0 <= k <= n.
(Sum_{k=0..n} T(n,k) * T(n,n-k))/T(n,n) = A193520(n) for n >= 0.
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