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A027356 Array read by rows: T(n,k) = number of partitions of n into distinct odd parts in which k is the greatest part, for k=1,2,...,n, n>=1. 6
1, 0, 0, 0, 0, 1, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 1, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 1, 0, 1, 0 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

First T(n,k) not 0 or 1 is T(17,9)=2, which counts 1+7+9 and 3+5+9. Row sums: A000700.

LINKS

Alois P. Heinz, Rows n = 1..361, flattened

Sean A. Irvine, Java program (github)

FORMULA

T(n, 1)=0 for all n; T(n, n)=1 for all odd n>1; and for n>=3, T(n, k)=0 if k is even, else T(n, k)=Sum{T(n-k, i): i=1, 2, ..., n-1} for k=2, 3, ..., n-1.

EXAMPLE

First 5 rows:

1

0 0

0 0 1

0 0 1 0

0 0 0 0 1

Row 40 with even-numbered terms deleted:

0 0 0 0 0 0 2 5 6 7 6 5 4 3 2 1 1 1 1;

E.g. final 2 counts these two partitions: 9+31 and 1+3+5+31.

MAPLE

b:= proc(n, i) option remember; `if`(n>i^2, 0, `if`(n=0, 1,

      b(n, i-1) +(p-> `if`(p>n, 0, b(n-p, i-1)))((2*i-1))))

    end:

T:= (n, k)-> `if`(k::even, 0, b(n-k, (k-1)/2)):

seq(seq(T(n, k), k=1..n), n=1..20);  # Alois P. Heinz, Oct 28 2019

MATHEMATICA

b[n_, i_] := b[n, i] = If[n > i^2, 0, If[n == 0, 1, b[n, i - 1] + Function[p, If[p > n, 0, b[n - p, i - 1]]][2i - 1]]];

T [n_, k_] := If[EvenQ[k], 0, b[n - k, (k - 1)/2]];

Table[Table[T[n, k], {k, 1, n}], {n, 1, 20}] // Flatten (* Jean-Fran├žois Alcover, Dec 06 2019, after Alois P. Heinz *)

CROSSREFS

Cf. A000700.

T(4n+1,2n+1) gives A069910.

Sequence in context: A288220 A173856 A288926 * A181663 A247223 A186741

Adjacent sequences:  A027353 A027354 A027355 * A027357 A027358 A027359

KEYWORD

nonn,tabl

AUTHOR

Clark Kimberling, revised Jul 23 2004

EXTENSIONS

Edited by N. J. A. Sloane, Sep 14 2008 at the suggestion of R. J. Mathar

STATUS

approved

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Last modified July 4 11:58 EDT 2020. Contains 335448 sequences. (Running on oeis4.)