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Number A(n,k) of partitions of n^k into parts that are at most n; square array A(n,k), n>=0, k>=0, read by antidiagonals.
+10
27
0, 1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 3, 3, 1, 1, 1, 5, 12, 5, 1, 1, 1, 9, 75, 64, 7, 1, 1, 1, 17, 588, 2280, 377, 11, 1, 1, 1, 33, 5043, 123464, 106852, 2432, 15, 1, 1, 1, 65, 44652, 7566280, 55567352, 6889527, 16475, 22, 1
OFFSET
0,9
COMMENTS
In general, for k>3, is column k asymptotic to exp(2*n) * n^((k-2)*n-k) / (2*Pi). For k=1 see A000041, for k=2 see A206226 and for k=3 see A238608. - Vaclav Kotesovec, May 25 2015
Conjecture: If f(n) >= O(n^4) then "number of partitions of f(n) into parts that are at most n" is asymptotic to f(n)^(n-1) / (n!*(n-1)!). See also A237998, A238000, A236810 or A258668-A258672. - Vaclav Kotesovec, Jun 07 2015
LINKS
FORMULA
A(n,k) = [x^(n^k)] Product_{j=1..n} 1/(1-x^j).
EXAMPLE
A(3,1) = 3: 3, 21, 111.
A(3,2) = 12: 333, 3222, 3321, 22221, 32211, 33111, 222111, 321111, 2211111, 3111111, 21111111, 111111111.
A(2,3) = 5: 2222, 22211, 221111, 2111111, 11111111.
A(2,4) = 9: 22222222, 222222211, 2222221111, 22222111111, 222211111111, 2221111111111, 22111111111111, 211111111111111, 1111111111111111.
Square array A(n,k) begins:
0, 1, 1, 1, 1, 1, ...
1, 1, 1, 1, 1, 1, ...
1, 2, 3, 5, 9, 17, ...
1, 3, 12, 75, 588, 5043, ...
1, 5, 64, 2280, 123464, 7566280, ...
1, 7, 377, 106852, 55567352, 33432635477, ...
MATHEMATICA
A[n_, k_] := SeriesCoefficient[Product[1/(1-x^j), {j, 1, n}], {x, 0, n^k}]; A[0, 0] = 0; Table[A[n-k, k], {n, 0, 10}, {k, n, 0, -1}] // Flatten (* Jean-François Alcover, Oct 11 2015 *)
CROSSREFS
Main diagonal gives A238000.
Cf. A238010.
KEYWORD
nonn,tabl
AUTHOR
Alois P. Heinz, Feb 17 2014
STATUS
approved
Number of partitions of n^3 into exactly n parts.
+10
6
1, 1, 4, 61, 1906, 91606, 6023602, 505853354, 51900711796, 6306147384659, 886745696653253, 141778041323736643, 25417656781153090889, 5052180112449982704619, 1103058286595668300801794, 262487324530101028337614478, 67628783852463631751658038290
OFFSET
0,3
LINKS
Chai Wah Wu, Table of n, a(n) for n = 0..136 (terms 0..96 from Alois P. Heinz)
FORMULA
a(n) = [x^(n^3-n)] Product_{k=1..n} 1/(1-x^k).
EXAMPLE
n | Partitions of n^3 into exactly n parts
--+------------------------------------------------------------
1 | 1.
2 | 7+1 = 6+2 = 5+3 = 4+4.
3 | 25+ 1+1 = 24+ 2+1 = 23+ 3+1 = 23+ 2+2 = 22+ 4+1 = 22+ 3+2
| = 21+ 5+1 = 21+ 4+2 = 21+ 3+3 = 20+ 6+1 = 20+ 5+2 = 20+ 4+3
| = 19+ 7+1 = 19+ 6+2 = 19+ 5+3 = 19+ 4+4 = 18+ 8+1 = 18+ 7+2
| = 18+ 6+3 = 18+ 5+4 = 17+ 9+1 = 17+ 8+2 = 17+ 7+3 = 17+ 6+4
| = 17+ 5+5 = 16+10+1 = 16+ 9+2 = 16+ 8+3 = 16+ 7+4 = 16+ 6+5
| = 15+11+1 = 15+10+2 = 15+ 9+3 = 15+ 8+4 = 15+ 7+5 = 15+ 6+6
| = 14+12+1 = 14+11+2 = 14+10+3 = 14+ 9+4 = 14+ 8+5 = 14+ 7+6
| = 13+13+1 = 13+12+2 = 13+11+3 = 13+10+4 = 13+ 9+5 = 13+ 8+6
| = 13+ 7+7 = 12+12+3 = 12+11+4 = 12+10+5 = 12+ 9+6 = 12+ 8+7
| = 11+11+5 = 11+10+6 = 11+ 9+7 = 11+ 8+8 = 10+10+7 = 10+ 9+8
| = 9+ 9+9.
MAPLE
b:= proc(n, i) option remember; `if`(n=0 or i=1, 1,
b(n, i-1)+b(n-i, min(i, n-i)))
end:
a:= n-> b(n^3-n, n):
seq(a(n), n=0..20); # Alois P. Heinz, May 07 2018
MATHEMATICA
$RecursionLimit = 2000;
b[n_, i_] := b[n, i] = If[n == 0 || i == 1, 1, b[n, i - 1] + b[n - i, Min[i, n - i]]];
a[n_] := b[n^3 - n, n];
a /@ Range[0, 20] (* Jean-François Alcover, Nov 23 2020, after Alois P. Heinz *)
PROG
(PARI) {a(n) = polcoeff(prod(k=1, n, 1/(1-x^k+x*O(x^(n^3-n)))), n^3-n)}
(Python)
import sys
from functools import lru_cache
sys.setrecursionlimit(10**6)
@lru_cache(maxsize=None)
def b(n, i): return 1 if n == 0 or i == 1 else b(n, i-1)+b(n-i, min(i, n-i))
def A304176(n): return b(n**3-n, n) # Chai Wah Wu, Sep 09 2021, after Alois P. Heinz
CROSSREFS
KEYWORD
nonn
AUTHOR
Seiichi Manyama, May 07 2018
STATUS
approved
Number of partitions of n*(n+1)*(n+2) into parts that are at most n.
+10
5
1, 1, 13, 331, 13561, 776594, 57773582, 5320252480, 586352480958, 75438829494131, 11116206652400681, 1848033852642973772, 342436117841931383400, 70020229273505952925559, 15667865938977592230047929, 3809417116914053901413289249, 1000291703885548521424635046427
OFFSET
0,3
LINKS
FORMULA
a(n) ~ exp(2*n + 13/4) * n^(n-3) / (2*Pi).
MAPLE
T:=proc(n, k) option remember; `if`(n=0 or k=1, 1, T(n, k-1) + `if`(n<k, 0, T(n-k, k))) end proc: seq(T(n*(n+1)*(n+2), n), n=0..20);
CROSSREFS
KEYWORD
nonn
AUTHOR
Vaclav Kotesovec, May 25 2015
STATUS
approved
Number of partitions of n*(n+1)*(n+2)/6 into parts that are at most n.
+10
5
1, 1, 3, 14, 108, 1115, 14800, 239691, 4602893, 102442041, 2596767156, 73937412122, 2338157235782, 81358388835166, 3090548185022616, 127310130911561966, 5654266354725389764, 269396637045530725099, 13708631585852580662781, 742141584297248778501411
OFFSET
0,3
LINKS
FORMULA
a(n) ~ exp(2*n + 9/2) * n^(n-3) / (2*Pi * 6^(n-1)).
MAPLE
T:=proc(n, k) option remember; `if`(n=0 or k=1, 1, T(n, k-1) + `if`(n<k, 0, T(n-k, k))) end proc: seq(T(n*(n+1)*(n+2)/6, n), n=0..20);
CROSSREFS
KEYWORD
nonn
AUTHOR
Vaclav Kotesovec, May 25 2015
STATUS
approved
Number of partitions of n*(n-1)*(n-2) into parts that are at most n.
+10
5
1, 1, 1, 7, 169, 7166, 436140, 34690401, 3418486403, 402588217564, 55217486292383, 8650673262689142, 1524827150449505994, 298774748146352115019, 64436825369109396329518, 15171417879016739747222223, 3872658124805520661780283663, 1065387724298834666633864592587
OFFSET
0,4
LINKS
FORMULA
a(n) ~ exp(2*n - 11/4) * n^(n-3) / (2*Pi).
MAPLE
T:=proc(n, k) option remember; `if`(n=0 or k=1, 1, T(n, k-1) + `if`(n<k, 0, T(n-k, k))) end proc: seq(T(n*(n-1)*(n-2), n), n=0..20);
CROSSREFS
KEYWORD
nonn
AUTHOR
Vaclav Kotesovec, May 25 2015
STATUS
approved
Number of partitions of n*(n-1)*(n-2)/6 into parts that are at most n.
+10
5
1, 1, 1, 1, 5, 30, 282, 3539, 55974, 1065947, 23785645, 608889106, 17594781914, 566603884871, 20123663539549, 781500841147604, 32946304088342094, 1498526109256063585, 73147202427442412812, 3814178439827570160925, 211598573411998923138880
OFFSET
0,5
LINKS
FORMULA
a(n) ~ exp(2*n - 3/2) * n^(n-3) / (2*Pi * 6^(n-1)).
MAPLE
T:=proc(n, k) option remember; `if`(n=0 or k=1, 1, T(n, k-1) + `if`(n<k, 0, T(n-k, k))) end proc: seq(T(n*(n-1)*(n-2)/6, n), n=0..20);
CROSSREFS
KEYWORD
nonn
AUTHOR
Vaclav Kotesovec, May 25 2015
STATUS
approved
Number of partitions of n*(n+1)*(2n+1)/6 into parts that are at most n.
+10
5
1, 1, 3, 24, 297, 5260, 123755, 3648814, 129828285, 5425234114, 260818130929, 14194798070042, 863357482347465, 58068803644110427, 4281318749672322843, 343463734454952001605, 29792472711307060688049, 2778959190056157071592315, 277420695604265258419161136
OFFSET
0,3
LINKS
FORMULA
a(n) ~ exp(2*n + 9/4) * n^(n-3) / (2*Pi * 3^(n-1)).
MAPLE
T:=proc(n, k) option remember; `if`(n=0 or k=1, 1, T(n, k-1) + `if`(n<k, 0, T(n-k, k))) end proc: seq(T(n*(n+1)*(2n+1)/6, n), n=0..20);
CROSSREFS
KEYWORD
nonn
AUTHOR
Vaclav Kotesovec, May 25 2015
STATUS
approved
Number of partitions of 2*n^3 into parts that are at most n.
+10
5
1, 1, 9, 271, 16335, 1525940, 196284041, 32409332818, 6561153029810, 1577073620254149, 439541281384464800, 139493983910450106067, 49695878602452933374813, 19646816226938989587513067, 8537966749269377751401117583, 4046350906270352192325991177139
OFFSET
0,3
LINKS
FORMULA
a(n) ~ exp(2*n + 1/8) * 2^(n-1) * n^(n-3) / (2*Pi).
MAPLE
T:=proc(n, k) option remember; `if`(n=0 or k=1, 1, T(n, k-1) + `if`(n<k, 0, T(n-k, k))) end proc: seq(T(2*n^3, n), n=0..20);
CROSSREFS
KEYWORD
nonn
AUTHOR
Vaclav Kotesovec, May 25 2015
STATUS
approved
Number of partitions of 3*n^3 into parts that are at most n.
+10
5
1, 1, 13, 588, 53089, 7431069, 1432812535, 354709605775, 107681683621061, 38815870525676822, 16224696168627992214, 7722681288635179285337, 4126484069454572889453794, 2446850787696893234909546422, 1594892857383186062141424302309
OFFSET
0,3
LINKS
FORMULA
a(n) ~ exp(2*n + 1/12) * 3^(n-1) * n^(n-3) / (2*Pi).
MAPLE
T:=proc(n, k) option remember; `if`(n=0 or k=1, 1, T(n, k-1) + `if`(n<k, 0, T(n-k, k))) end proc: seq(T(3*n^3, n), n=0..20);
CROSSREFS
KEYWORD
nonn
AUTHOR
Vaclav Kotesovec, May 25 2015
STATUS
approved
Number of partitions of 4*n^3 into parts that are at most n.
+10
5
1, 1, 17, 1027, 123464, 23030612, 5918918145, 1953335236481, 790541795804221, 379916850888632162, 211720519858133280231, 134359691058417334173117, 95719564240981718602134049, 75674822191817499226090337378, 65766024754772296807292428860854
OFFSET
0,3
LINKS
FORMULA
a(n) ~ exp(2*n + 1/16) * 4^(n-1) * n^(n-3) / (2*Pi).
MAPLE
T:=proc(n, k) option remember; `if`(n=0 or k=1, 1, T(n, k-1) + `if`(n<k, 0, T(n-k, k))) end proc: seq(T(4*n^3, n), n=0..20);
CROSSREFS
KEYWORD
nonn
AUTHOR
Vaclav Kotesovec, May 25 2015
STATUS
approved

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