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 1-2 of 2 results.

A292860 Square array A(n,k), n>=0, k>=0, read by antidiagonals downwards, where column k is the expansion of e.g.f. exp(k*(exp(x) - 1)).

Original entry on oeis.org

1, 1, 0, 1, 1, 0, 1, 2, 2, 0, 1, 3, 6, 5, 0, 1, 4, 12, 22, 15, 0, 1, 5, 20, 57, 94, 52, 0, 1, 6, 30, 116, 309, 454, 203, 0, 1, 7, 42, 205, 756, 1866, 2430, 877, 0, 1, 8, 56, 330, 1555, 5428, 12351, 14214, 4140, 0, 1, 9, 72, 497, 2850, 12880, 42356, 88563, 89918, 21147, 0
Offset: 0

Views

Author

Seiichi Manyama, Sep 25 2017

Keywords

Examples

			Square array begins:
   1,   1,    1,     1,     1,      1,      1, ...
   0,   1,    2,     3,     4,      5,      6, ...
   0,   2,    6,    12,    20,     30,     42, ...
   0,   5,   22,    57,   116,    205,    330, ...
   0,  15,   94,   309,   756,   1555,   2850, ...
   0,  52,  454,  1866,  5428,  12880,  26682, ...
   0, 203, 2430, 12351, 42356, 115155, 268098, ...
		

Crossrefs

Rows n=0..2 give A000012, A001477, A002378.
Main diagonal gives A242817.
Same array, different indexing is A189233.
Cf. A292861.

Programs

  • Maple
    A:= proc(n, k) option remember; `if`(n=0, 1,
          (1+add(binomial(n-1, j-1)*A(n-j, k), j=1..n-1))*k)
        end:
    seq(seq(A(n, d-n), n=0..d), d=0..12);  # Alois P. Heinz, Sep 25 2017
  • Mathematica
    A[0, ] = 1; A[n /; n >= 0, k_ /; k >= 0] := A[n, k] = k*Sum[Binomial[n-1, j]*A[j, k], {j, 0, n-1}]; A[, ] = 0;
    Table[A[n, d - n], {d, 0, 12}, {n, 0, d}] // Flatten (* Jean-François Alcover, Feb 13 2021 *)
    A292860[n_, k_] := BellB[n, k]; Table[A292860[k, n - k], {n, 0, 10}, {k, 0, n}] // Flatten (* Peter Luschny, Dec 23 2021 *)

Formula

A(0,k) = 1 and A(n,k) = k * Sum_{j=0..n-1} binomial(n-1,j) * A(j,k) for n > 0.
A(n,k) = Sum_{j=0..n} k^j * Stirling2(n,j). - Seiichi Manyama, Jul 27 2019
A(n,k) = BellPolynomial(n, k). - Peter Luschny, Dec 23 2021

A276507 E.g.f.: exp(10*(exp(x)-1)).

Original entry on oeis.org

1, 10, 110, 1310, 16710, 226510, 3243110, 48807310, 768988710, 12641850510, 216229931110, 3838516103310, 70569453740710, 1341065189434510, 26298323383739110, 531365183231239310, 11047184452086972710, 236029124143560378510, 5176602413033115467110
Offset: 0

Views

Author

Vincenzo Librandi, Sep 19 2016

Keywords

Comments

Number of ways of placing n labeled balls into n unlabeled (but 10-colored) boxes.

Crossrefs

Cf. similar sequences listed in A276506.

Programs

  • Maple
    a:= proc(n) option remember; `if`(n=0, 1,
          (1+add(binomial(n-1, k-1)*a(n-k), k=1..n-1))*10)
        end:
    seq(a(n), n=0..25);  # Alois P. Heinz, Sep 25 2017
  • Mathematica
    Table[BellB[n, 10], {n, 0, 30}]
  • PARI
    my(x='x+O('x^99)); Vec(serlaplace(exp(10*(exp(x)-1)))) \\ Altug Alkan, Sep 19 2016

Formula

G.f.: A(x) satisfies 10*(x/(1-x))*A(x/(1-x)) = A(x)-1; ten times the binomial transform equals this sequence shifted one place left.
Showing 1-2 of 2 results.