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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.

A351725 Table T(n,k) read by rows: number of partitions of n into k parts of size 1, 5, 10 or 25.

Original entry on oeis.org

1, 0, 1, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 1, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 1, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 1, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 1, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 1, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 1, 1, 0, 0, 1, 1, 0, 0, 0, 1, 0, 0, 0, 1
Offset: 0

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Author

R. J. Mathar, Feb 17 2022

Keywords

Comments

Multiset transform of the binary sequence b(n)=1,1,0,0,0,1,0,0,0,0,1,0,... with g.f. 1 + x + x^5 + x^10 + x^25, where b(.) is the Inverse Euler Transform of A001299.

Examples

			T(30,6)=2 counts the partitions 5+5+5+5+5+5 = 1+1+1+1+1+25.
The triangle starts at row n=0 and has columns k=0..n:
1
0 1
0 0 1
0 0 0 1
0 0 0 0 1
0 1 0 0 0 1
0 0 1 0 0 0 1
0 0 0 1 0 0 0 1
0 0 0 0 1 0 0 0 1
0 0 0 0 0 1 0 0 0 1
0 1 1 0 0 0 1 0 0 0 1
0 0 1 1 0 0 0 1 0 0 0 1
0 0 0 1 1 0 0 0 1 0 0 0 1
0 0 0 0 1 1 0 0 0 1 0 0 0 1
0 0 0 0 0 1 1 0 0 0 1 0 0 0 1
0 0 1 1 0 0 1 1 0 0 0 1 0 0 0 1
0 0 0 1 1 0 0 1 1 0 0 0 1 0 0 0 1
0 0 0 0 1 1 0 0 1 1 0 0 0 1 0 0 0 1
0 0 0 0 0 1 1 0 0 1 1 0 0 0 1 0 0 0 1
0 0 0 0 0 0 1 1 0 0 1 1 0 0 0 1 0 0 0 1
0 0 1 1 1 0 0 1 1 0 0 1 1 0 0 0 1 0 0 0 1
0 0 0 1 1 1 0 0 1 1 0 0 1 1 0 0 0 1 0 0 0 1
0 0 0 0 1 1 1 0 0 1 1 0 0 1 1 0 0 0 1 0 0 0 1
0 0 0 0 0 1 1 1 0 0 1 1 0 0 1 1 0 0 0 1 0 0 0 1
0 0 0 0 0 0 1 1 1 0 0 1 1 0 0 1 1 0 0 0 1 0 0 0 1
0 1 0 1 1 1 0 1 1 1 0 0 1 1 0 0 1 1 0 0 0 1 0 0 0 1
0 0 1 0 1 1 1 0 1 1 1 0 0 1 1 0 0 1 1 0 0 0 1 0 0 0 1
0 0 0 1 0 1 1 1 0 1 1 1 0 0 1 1 0 0 1 1 0 0 0 1 0 0 0 1
0 0 0 0 1 0 1 1 1 0 1 1 1 0 0 1 1 0 0 1 1 0 0 0 1 0 0 0 1
0 0 0 0 0 1 0 1 1 1 0 1 1 1 0 0 1 1 0 0 1 1 0 0 0 1 0 0 0 1
0 0 1 1 1 1 2 0 1 1 1 0 1 1 1 0 0 1 1 0 0 1 1 0 0 0 1 0 0 0 1
		

Crossrefs

Cf. A001299 (row sums), A351740.
Column k=0 gives A000007.
Main diagonal gives A000012.
T(2n,n) gives A351742.

Programs

  • Maple
    b:= proc(n, i) option remember; `if`(n=0 or i=1, x^n, b(n, i-1)+
         (p-> `if`(p>n, 0, expand(x*b(n-p, i))))([1, 5, 10, 25][i]))
        end:
    T:= n-> (p-> seq(coeff(p, x, i), i=0..n))(b(n, 4)):
    seq(T(n), n=0..15);  # Alois P. Heinz, Feb 17 2022
  • Mathematica
    b[n_, i_] := b[n, i] = If[n == 0 || i == 1, x^n, b[n, i - 1] +
         Function[p, If[p > n, 0, Expand[x*b[n-p, i]]]][{1, 5, 10, 25}[[i]]]];
    T[n_] := Function[p, Table[Coefficient[p, x, i], {i, 0, n}]][b[n, 4]];
    Table[T[n], {n, 0, 15}] // Flatten (* Jean-François Alcover, May 16 2022, after Alois P. Heinz *)

Formula

T(n,0) = 0 if k>0.
T(n,n) = 1.
Sum_{k=0..n} k * T(n,k) = A351740(n). - Alois P. Heinz, Feb 17 2022