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 1-8 of 8 results.

A108291 Triangle, read by rows, resulting from the matrix product of triangle A108267 with Pascal's triangle (A007318).

Original entry on oeis.org

1, 2, 1, 9, 9, 1, 64, 96, 34, 1, 625, 1250, 750, 125, 1, 7776, 19440, 16470, 5265, 461, 1, 117649, 352947, 386561, 184877, 35329, 1715, 1, 2097152, 7340032, 9863168, 6307840, 1913408, 232288, 6434, 1, 43046721, 172186884, 274223556, 220016574
Offset: 0

Views

Author

Paul D. Hanna, May 31 2005

Keywords

Comments

Row sums form A108292. Column 0 is A000169(n) = (n+1)^n. Triangle with rows reversed is A108290.

Examples

			Triangle begins:
1;
2,1;
9,9,1;
64,96,34,1;
625,1250,750,125,1;
7776,19440,16470,5265,461,1;
117649,352947,386561,184877,35329,1715,1;
2097152,7340032,9863168,6307840,1913408,232288,6434,1; ...
		

Crossrefs

Programs

  • PARI
    {T(n,k)=local(X=x+x*O(x^(n-k))); polcoeff(sum(j=0,n,binomial(n+n*j+j,n*j+j)*(x/(1+X))^j)/(1+X),n-k)}

A108268 Column 2 of triangle A108267.

Original entry on oeis.org

1, 31, 381, 3431, 26769, 193705, 1343521, 9091270, 60632419, 401001030, 2639871326, 17339260251, 113792427233, 746807661549, 4903854042841, 32227106641988, 211992209767971, 1395903036647155, 9200826759772935
Offset: 2

Views

Author

Paul D. Hanna, May 29 2005

Keywords

Crossrefs

Cf. A108267.

Programs

  • PARI
    a(n)=polcoeff((1-x)^(n+1)*sum(j=0,n,binomial(n+n*j+j,n*j+j)*x^j),2)

Extensions

Offset corrected by Andrey Zabolotskiy, Nov 23 2021

A060543 Triangle, read by antidiagonals, where T(n,k) = C(n+n*k+k, n*k+k).

Original entry on oeis.org

1, 1, 1, 1, 3, 1, 1, 10, 5, 1, 1, 35, 28, 7, 1, 1, 126, 165, 55, 9, 1, 1, 462, 1001, 455, 91, 11, 1, 1, 1716, 6188, 3876, 969, 136, 13, 1, 1, 6435, 38760, 33649, 10626, 1771, 190, 15, 1, 1, 24310, 245157, 296010, 118755, 23751, 2925, 253, 17, 1, 1, 92378, 1562275
Offset: 0

Views

Author

Henry Bottomley, Apr 02 2001

Keywords

Comments

Main diagonal is A108288. Antidiagonal sums is A108289. Inverse binomial transforms of each row give triangle A108290. G.f. of row n multiplied by (1-x)^(n+1) equals g.f. of row n of triangle A108267 (rows sums of A108267 equal (n+1)^n).

Examples

			row 1: (2*n+1)/1!
row 2: (3*n+1)*(3*n+2)/2!
row 3: (4*n+1)*(4*n+2)*(4*n+3)/3!
row 4: (5*n+1)*(5*n+2)*(5*n+3)*(5*n+4)/4!
row 5: (6*n+1)*(6*n+2)*(6*n+3)*(6*n+4)*(6*n+5)/5!.
Table begins:
1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,...
1,3,5,7,9,11,13,15,17,19,21,23,25,27,...
1,10,28,55,91,136,190,253,325,406,496,...
1,35,165,455,969,1771,2925,4495,6545,...
1,126,1001,3876,10626,23751,46376,82251,...
1,462,6188,33649,118755,324632,749398,...
1,1716,38760,296010,1344904,4496388,...
		

Crossrefs

Cf. A108290, A108267, A108288, A108289, A060544 (row 2), A015219 (row 3).
Rows include A000012, A001700, A025174. Columns include A000012, A005408, A060544. Main diagonal is A060545.

Programs

  • PARI
    T(n,k)=binomial(n+n*k+k,n*k+k)
    
  • PARI
    { i=0; write("b060543.txt", "0 1"); for (m=0, 20, for (k=0, m + 1, n=m - k + 1; write("b060543.txt", i++, " ", binomial(n + n*k + k, n*k + k))); ) } \\ Harry J. Smith, Jul 06 2009

Formula

a(n) = A060539(n, k)/n = A007318(nk, k)/n = A060540(n, k)/A060540(n-1, k).

Extensions

Entry revised by Paul D. Hanna, May 31 2005
Edited by N. J. A. Sloane at the suggestion of Andrew S. Plewe, Jun 17 2007

A108290 Triangle, read by rows, such that row n equals the inverse binomial transform of row n of table A060543, where A060543(n,k) = C(n+n*k+k, n*k+k).

Original entry on oeis.org

1, 1, 2, 1, 9, 9, 1, 34, 96, 64, 1, 125, 750, 1250, 625, 1, 461, 5265, 16470, 19440, 7776, 1, 1715, 35329, 184877, 386561, 352947, 117649, 1, 6434, 232288, 1913408, 6307840, 9863168, 7340032, 2097152, 1, 24309, 1513656, 18921924, 92365758, 220016574
Offset: 0

Views

Author

Paul D. Hanna, May 31 2005

Keywords

Comments

Row sums form A108292. Main diagonal is A000169(n) = (n+1)^n. Triangle with rows reversed is A108291.
The rows seem to give (up to sign) the coefficients in the expansion of the integer-valued polynomial (1+n*x)*(2+n*x)*...*(n-1+n*x)/(n-1)! in the basis made of the binomial(x+i,i). - F. Chapoton, Nov 01 2022

Examples

			BINOMIAL[1, 9, 9] = {1, 10, 28, 55, 91, 136, 190, 253, ...}.
BINOMIAL[1, 34, 96, 64] = {1, 35, 165, 455, 969, 1771, 2925, ...}.
BINOMIAL[1, 125, 750, 1250, 625] = {1, 126, 1001, 3876, 10626, ...}.
Triangle begins:
  1;
  1,    2;
  1,    9,      9;
  1,   34,     96,      64;
  1,  125,    750,    1250,     625;
  1,  461,   5265,   16470,   19440,    7776;
  1, 1715,  35329,  184877,  386561,  352947,  117649;
  1, 6434, 232288, 1913408, 6307840, 9863168, 7340032, 2097152; ...
		

Crossrefs

Programs

  • PARI
    {T(n,k)=local(X=x+x*O(x^k)); polcoeff(sum(j=0,n,binomial(n+n*j+j,n*j+j)*(x/(1+X))^j)/(1+X),k)}

A108292 Row sums of triangle A108290.

Original entry on oeis.org

1, 3, 19, 195, 2751, 49413, 1079079, 27760323, 822299383, 27565191753, 1031671508495, 42643092165765, 1929325374428791, 94835735736471369, 5032700868665421519, 286770182910733076163, 17463186681730290301671
Offset: 0

Views

Author

Paul D. Hanna, May 31 2005

Keywords

Crossrefs

Programs

  • PARI
    a(n)=local(X=x+x*O(x^n));sum(k=0,n, polcoeff(sum(j=0,n,binomial(n+n*j+j,n*j+j)*(x/(1+X))^j)/(1+X),k))
    
  • PARI
    a(n)=sum(k=0,n,2^k*polcoeff( (1-x)^(n+1)*sum(j=0,n,binomial(n+n*j+j,n*j+j)*x^j),k))

Formula

a(n) = Sum_{k=0..n} A108267(n, k)*2^k.

A108288 Main diagonal of table A060543; a(n) = C((n+1)^2-1, n*(n+1)).

Original entry on oeis.org

1, 3, 28, 455, 10626, 324632, 12271512, 553270671, 28987537150, 1731030945644, 116068178638776, 8634941152058949, 705873715441872264, 62895036884524942320, 6067037854078498539696, 629921975126394617164575, 70043473196734767582082230
Offset: 0

Views

Author

Paul D. Hanna, May 31 2005

Keywords

Crossrefs

Programs

  • PARI
    a(n)=binomial((n+1)^2-1,n*(n+1))

Formula

a(n) = A060545(n+1). - R. J. Mathar, Aug 24 2008

A108289 Antidiagonal sums of table A060543.

Original entry on oeis.org

1, 2, 5, 17, 72, 357, 2022, 12900, 91448, 711180, 6004981, 54619489, 531854438, 5515551251, 60642234815, 704106298738, 8603658260904, 110306422692488, 1479905106340895, 20727595895871297, 302423908621734606
Offset: 0

Views

Author

Paul D. Hanna, May 31 2005

Keywords

Crossrefs

Programs

  • PARI
    a(n)=sum(k=0,n,binomial(n+(n-k)*k,(n-k)*k+k))

Formula

a(n)=Sum_{k=0..n} C(n+(n-k)*k, (n-k)*k+k).

A333829 Triangle read by rows: T(n,k) is the number of parking functions of length n with k strict descents. T(n,k) for n >= 1 and 0 <= k <= n-1.

Original entry on oeis.org

1, 2, 1, 5, 10, 1, 14, 73, 37, 1, 42, 476, 651, 126, 1, 132, 2952, 8530, 4770, 422, 1, 429, 17886, 95943, 114612, 31851, 1422, 1, 1430, 107305, 987261, 2162033, 1317133, 202953, 4853, 1, 4862, 642070, 9613054, 35196634, 39471355, 13792438, 1262800, 16786, 1
Offset: 1

Views

Author

Keywords

Comments

In a parking function w(1), ..., w(n), a strict descent is an index i such that w(i) > w(i+1).
Define an n-dimensional polytope as the convex hull of length n+1 nondecreasing parking functions. Then, the Ehrhart h*-polynomial of this polytope is Sum_{k=0..n-1} T(n,k) * z^(n-1-k).

Examples

			The triangle T(n,k) begins:
n/k  0    1    2    3    4    5
1    1
2    2    1
3    5   10    1
4   14   73   37    1
5   42  476  651  126    1
6  132 2952 8530 4770  422    1
...
The 10 parking functions of length 3 with 1 strict descent are: [[1, 2, 1], [2, 1, 1], [1, 3, 1], [3, 1, 1], [2, 1, 2], [2, 2, 1], [1, 3, 2], [2, 1, 3], [2, 3, 1], [3, 1, 2]].
		

Crossrefs

Row sums give A000272(n+1).
Column k=0 gives A000108.
Similar to A108267.

Programs

  • SageMath
    var('z,t')
    assume(0
    				
  • SageMath
    # using[latte_int from LattE]
    # Install with "sage -i latte_int".
    # Another method is to compute the Ehrhart h^*-polynomial of a polytope.
    var('z,t')
    def Tpol(n):
        p = Polyhedron( NonDecreasingParkingFunctions(n+1) ).ehrhart_polynomial()
        return expand(factor( (1-z)**(n+1) * sum( p * z**t , t , 0 , oo ) ))
    def T(n,k):
        return Tpol(n).list()[n-1-k]
Showing 1-8 of 8 results.