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.

A061198 Square table by antidiagonals where T(n,k) is number of partitions of k where no part appears more than n times; also partitions of k where no parts are multiples of (n+1).

Original entry on oeis.org

1, 0, 1, 0, 1, 1, 0, 1, 1, 1, 0, 2, 2, 1, 1, 0, 2, 2, 2, 1, 1, 0, 3, 4, 3, 2, 1, 1, 0, 4, 5, 4, 3, 2, 1, 1, 0, 5, 7, 6, 5, 3, 2, 1, 1, 0, 6, 9, 9, 6, 5, 3, 2, 1, 1, 0, 8, 13, 12, 10, 7, 5, 3, 2, 1, 1, 0, 10, 16, 16, 13, 10, 7, 5, 3, 2, 1, 1, 0, 12, 22, 22, 19, 14, 11, 7, 5, 3, 2, 1, 1, 0, 15, 27, 29, 25, 20, 14, 11, 7, 5, 3, 2, 1, 1
Offset: 0

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Author

Henry Bottomley, Apr 20 2001

Keywords

Examples

			Square table T(n,k) begins:
  1, 0, 0, 0, 0, 0,  0,  0,  0,  0,  0, ...
  1, 1, 1, 2, 2, 3,  4,  5,  6,  8, 10, ...
  1, 1, 2, 2, 4, 5,  7,  9, 13, 16, 22, ...
  1, 1, 2, 3, 4, 6,  9, 12, 16, 22, 29, ...
  1, 1, 2, 3, 5, 6, 10, 13, 19, 25, 34, ...
  1, 1, 2, 3, 5, 7, 10, 14, 20, 27, 37, ...
  1, 1, 2, 3, 5, 7, 11, 14, 21, 28, 39, ...
  1, 1, 2, 3, 5, 7, 11, 15, 21, 29, 40, ...
  1, 1, 2, 3, 5, 7, 11, 15, 22, 29, 41, ...
  1, 1, 2, 3, 5, 7, 11, 15, 22, 30, 41, ...
  1, 1, 2, 3, 5, 7, 11, 15, 22, 30, 42, ...
		

Crossrefs

Rows include A000007, A000009, A000726, A035959.
Main diagonal is A000041.
A061199 is the same table but excluding cases where n>k.
Cf. A286653.

Programs

  • Maple
    b:= proc(n, i, k) option remember; `if`(n=0, 1, `if`(i<1, 0,
          add(b(n-i*j, i-1, k), j=0..min(n/i, k))))
        end:
    A:= (n, k)-> b(k$2, n):
    seq(seq(A(n, d-n), n=0..d), d=0..13);  # Alois P. Heinz, Jan 26 2023
  • Mathematica
    b[n_, i_, k_] := b[n, i, k] = If[n == 0, 1, If[i<1, 0, Sum[b[n-i*j, i-1, k], {j, 0, Min[n/i, k]}]]];
    A[n_, k_] := b[k, k, n];
    Table[Table[A[n, d-n], {n, 0, d}], {d, 0, 13}] // Flatten (* Jean-François Alcover, Feb 11 2023, after Alois P. Heinz *)

Formula

G.f. for row n of table: Product_{j>=1} Sum_{k=0..n} x^(j*k) = Product_{j>=1} (1-x^((n+1)*j)) / (1-x^j). - Sean A. Irvine, Jan 26 2023