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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.

A082914 a(n) = n! / A003040(n).

Original entry on oeis.org

1, 2, 3, 8, 20, 45, 144, 448, 1680, 4725, 17280, 62208, 290304, 1254400, 4465125, 18144000, 72990720, 391910400, 1881169920, 9754214400, 45660160000, 205752960000, 905748480000, 5280992640000, 28326238617600, 162956344320000, 853298675712000, 5309413982208000
Offset: 1

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Author

Yuval Dekel (dekelyuval(AT)hotmail.com), May 25 2003

Keywords

Comments

Minimum product of hook lengths of a partition of n. - Eric M. Schmidt, May 07 2013

Examples

			For n=4, we can have
abcd, abc and ab (the rest are symmetric).
......d.......cd
The hook products are 4! = 24, 4*2*1*1 = 8 and 3*2*2*1 = 12, so a(4) = 8. - _Jon Perry_
		

Crossrefs

Cf. A003040.

Programs

  • Maple
    # Maple code from  Emeric Deutsch, May 12 2004 (Start)
    H:=proc(pa) local F,j,p,Q,i,col,a,A: F:=proc(x) local i, ct: ct:=0: for i from 1 to nops(x) do if x[i]>1 then ct:=ct+1 else fi od: ct; end:
    for j from 1 to nops(pa) do p[1][j]:=pa[j] od: Q[1]:=[seq(p[1][j],j=1..nops(pa))]:
    for i from 2 to pa[1] do for j from 1 to F(Q[i-1]) do p[i][j]:=Q[i-1][j]-1 od:
    Q[i]:=[seq(p[i][j],j=1..F(Q[i-1]))] od:
    for i from 1 to pa[1] do col[i]:=[seq(Q[i][j]+ nops(Q[i])-j,j=1..nops(Q[i]))] od:
    a:=proc(i,j) if i<=nops(Q[j]) and j<=pa[1] then Q[j][i]+nops(Q[j])-i else 1 fi end:
    A:=matrix(nops(pa),pa[1],a): product(product(A[m,n],n=1..pa[1]),m=1..nops(pa)); end:
    with(combinat):
    rev:=proc(a) [seq(a[nops(a)+1-i],i=1..nops(a))] end:
    seq(sort([seq(H(rev(partition(j)[i])),i=1..numbpart(j))])[1],j=1..30);
    # the procedure H gives the hook product for a given partition written with parts in nonincreasing order;
    # if in the definition of the procedure a we replace "else 1" by "else x", then the matrix A yields all the hooklengths corresponding to a partition.
    # (End)

Extensions

More terms from Eric M. Schmidt, May 07 2013