cp's OEIS Frontend

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.

Showing 1-3 of 3 results.

A169667 The classical Lie superfactorial of types E6, E7, E8.

Original entry on oeis.org

23361421521715200000, 19403468278119790545603479218421760000000000, 12389761771281087987161913865011039548629176646031786340025309566313679656889905840128000000000000000000000
Offset: 1

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Author

Robert Coquereaux, Apr 05 2010

Keywords

Comments

When a Lie group G is simply laced, the classical Lie superfactorial sf_G is the product of s! where s belongs to the multiset E of exponents of G. Here G=E6, E7, E8. When G is exceptional of type E (this case), the Lie superfactorial does not define an infinite sequence: it has only three terms.
To every simple Lie group G one can associate both a quantum and a classical superfactorial of type G.
The classical Lie superfactorial of type G, denoted sf_G, is defined as the classical limit (q-->1) of the quantum Weyl denominator of G.
If G is simply laced (ADE Dynkin diagrams) i.e. Ar,Dr,E6,E7,E8 cases, the integer sf_G is the product of s!, where s runs over the multiset of exponents of G.
The usual superfactorial r --> sf[r] is recovered as the Lie superfactorial r --> sf_{Ar} of type Ar [nonascii characters here] SU(r+1), sequence A000178.
The superfactorial of type Dr [nonascii characters here] SO(2r) defines the infinite sequence A169657.
Since there are only three simply laced exceptional Lie groups, the r --> sf_{Er} sequence has only three terms.
If G is not simply laced, i.e. Br, Cr, G2 or F4 cases, the Lie superfactorial is also simply related to the product of factorials s! where s belongs to the multiset E of exponents of G. See sequence A169668.
The classical Lie superfactorial of type G enters the asymptotic expression giving the global dimension of a monoidal category of type G at level k, when k is large.
Call gamma the Coxeter number of G, r its rank, Delta the determinant of the fundamental quadratic form, and dim(G) its dimension, the asymptotic expression reads: k^dim(G) / ((2 pi)^(r gamma) Delta (sf_G)^2 ).

Crossrefs

A000178 gives sf_G for G=Ar=SU(r+1). A169657 gives sf_G for G=Dr~SO(2r). A169668 describes sf_G for non-simply laced cases.

Formula

sf_{E6} = 1! 4! 5! 7! 8! 11!.
sf_{E7} = 1! 5! 7! 9! 11! 13! 17!.
sf_{E8} = 1! 7! 11! 13! 17! 19! 23! 29!.

A169668 The product of factorials s! where s belongs to the multiset of exponents of the Lie groups G=Br or G=Cr. Also 2^r times the classical Lie superfactorial of type Br ~ SO(2r+1). Also 2^{r(r-1)} times the Lie superfactorial of type Cr ~ Sp(2r).

Original entry on oeis.org

6, 720, 3628800, 1316818944000, 52563198423859200000, 327312129899898454671360000000, 428017682605583614976547335700480000000000
Offset: 2

Views

Author

Robert Coquereaux, Apr 05 2010

Keywords

Comments

To every simple Lie group G one can associate both a quantum and a classical superfactorial of type G.
The classical Lie superfactorial of type G , denoted sf_G, is defined as the classical limit (q-->1) of the quantum Weyl denominator of G.
If G is simply laced (ADE Dynkin diagrams), i.e., Ar,Dr,E6,E7,E8 cases, the integer sf_G is the product of factorial s!, where s runs over the multiset of exponents of G.
The usual superfactorial r --> sf[r] is recovered as the Lie superfactorial r --> sf_{Ar} of type Ar [nonascii characters here] SU(r+1), sequence A000178.
The superfactorial of type Dr [nonascii characters here] SO(2r) defines the infinite sequence A169657.
If G is exceptional of type E, the Lie superfactorial defines a sequence with only three terms, see sequence A169667.
If G is not simply laced, i.e., Br (this case), Cr (this case), G2 or F4, the Lie superfactorial differs by simple pre-factors from the product of factorials of exponents.
If G=Br ~ SO(2r+1), the pre-factor is 1/2^r and r --> sf_{Br} = (1/2^r) Product_{s \in 1,3,5,.., 2r-1} s!
If G = Cr ~ Sp(2r), the pre-factor is 1/2^{r(r-1)} and r --> sf_{Cr} = (1/2^{r(r-1)}) Product_{s \in 1,3,5,.., 2r-1} s!
If G = F4, sf_{F4} = 1/2^{12} 1! 5! 7! 11! = 5893965000 (a sequence with only one term).
If G = G2, sf_{G2} = 1/3^{3} 1! 5! = 40/9 (a sequence with only one term).
The classical Lie superfactorial of type G enters the asymptotic expression giving the global dimension of a monoidal category of type G at level k, when k is large.
Call gamma the Coxeter number of G, r its rank, Delta the determinant of the fundamental quadratic form, and dim(G) its dimension, the asymptotic expression reads : k^dim(G) / ((2 pi)^(r gamma) Delta (sf_G)^2 ).

Crossrefs

A000178 gives sf_G for G=Ar=SU(r+1). A169657 gives sf_G for G=Dr~SO(2r). A169667 gives sf_G for G=E6, E7, E8.

Programs

  • Mathematica
    Product[Factorial[s], {s, 1, (2 r - 1), 2}]

Formula

Product_{s \in 1,3,5,.., 2r-1} s!
a(n) ~ 2^(n^2 + n + 5/24) * n^(n^2 + n/2 - 1/24) * Pi^(n/2) / (sqrt(A) * exp(n*(3*n+1)/2 - 1/24)), where A is the Glaisher-Kinkelin constant A074962. - Vaclav Kotesovec, Mar 05 2021

A096732 a(n)=det(M_n) where M_n is the n X n matrix m(i,j)=i^j*j^i.

Original entry on oeis.org

1, 12, 4284, 84720384, 148993369113600, 34155172566092379340800, 1406681240638328150516203644518400, 13722109275339434419337247034130459935742361600
Offset: 1

Views

Author

Benoit Cloitre, May 30 2002

Keywords

Crossrefs

Programs

  • Mathematica
    Table[Det[Table[i^j j^i,{i,n},{j,n}]],{n,8}] (* Harvey P. Dale, Jun 26 2021 *)
  • PARI
    for(n=1,10,print1(matdet(matrix(n,n,i,j,i^j*j^i)),","))

Formula

Conjecture: lim_{n->oo} a(n)^(1/n^2)/n = 2*exp(-3/2). - Vaclav Kotesovec, Apr 19 2024
Showing 1-3 of 3 results.