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A255212
Number A(n,k) of partitions of n^2 into at most k square parts; square array A(n,k), n>=0, k>=0, read by antidiagonals.
12
1, 1, 0, 1, 1, 0, 1, 1, 1, 0, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 0, 1, 1, 2, 2, 1, 1, 0, 1, 1, 2, 2, 1, 2, 1, 0, 1, 1, 2, 2, 2, 2, 1, 1, 0, 1, 1, 2, 3, 3, 3, 2, 1, 1, 0, 1, 1, 2, 3, 3, 4, 4, 2, 1, 1, 0, 1, 1, 2, 3, 4, 5, 5, 4, 1, 1, 1, 0, 1, 1, 2, 4, 5, 7, 9, 6, 2, 4, 2, 1, 0
OFFSET
0,24
LINKS
EXAMPLE
Square array A(n,k) begins:
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, ...
0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, ...
0, 1, 1, 1, 2, 2, 2, 2, 2, 2, 2, ...
0, 1, 1, 2, 2, 2, 3, 3, 3, 4, 4, ...
0, 1, 1, 1, 2, 3, 3, 4, 5, 5, 6, ...
0, 1, 2, 2, 3, 4, 5, 7, 8, 9, 11, ...
0, 1, 1, 2, 4, 5, 9, 10, 11, 15, 17, ...
0, 1, 1, 2, 4, 6, 9, 13, 18, 21, 27, ...
0, 1, 1, 1, 2, 7, 9, 16, 25, 30, 41, ...
0, 1, 1, 4, 6, 8, 18, 27, 36, 52, 68, ...
0, 1, 2, 2, 7, 13, 23, 36, 51, 70, 94, ...
MAPLE
b:= proc(n, i, t) option remember; `if`(n=0 or i=1 and n<=t, 1,
(j-> `if`(t*j<n, 0, b(n, i-1, t)+
`if`(j>n, 0, b(n-j, i, t-1))))(i^2))
end:
A:= (n, k)-> b(n^2, n, k):
seq(seq(A(n, d-n), n=0..d), d=0..15);
MATHEMATICA
b[n_, i_, t_] := b[n, i, t] = If[n == 0 || i == 1 && n <= t, 1, Function[j, If[t*j<n, 0, b[n, i-1, t] + If[j>n, 0, b[n-j, i, t-1]]]][i^2]]; A[n_, k_] := b[n^2, n, k]; Table[Table[A[n, d - n], {n, 0, d}], {d, 0, 15}] // Flatten (* Jean-François Alcover, Feb 22 2016, after Alois P. Heinz *)
CROSSREFS
Main diagonal gives A105152.
Cf. A302996.
Sequence in context: A099918 A099860 A317950 * A323011 A327747 A282750
KEYWORD
nonn,tabl
AUTHOR
Alois P. Heinz, Feb 17 2015
STATUS
approved