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SandBoxFormalProduct ←	↑	→ SandBoxFractionGCD

SandBoxFormann

Edit detail for SandBoxFormann revision 1 of 1

	1
Editor: Time: 2007/11/18 18:02:23 GMT-8
Note:

changed:
-
f calculates the number of 0-1 matrices with row sums 'A' and column sums 'B'. 

\begin{axiom}
f(A:List PI, B:List PI): FRAC INT == cap(reduce(*, [elementary i for i in A]), reduce(*, [complete i for i in B]))
\end{axiom}

For example, there are
\begin{axiom}
f([2,2,2,2], [2,3,3])
\end{axiom}

0-1 matrices whose rows all sum up to two and whose first column has 2 entries equal to one, the others having 3 entries equal to one.

f calculates the number of 0-1 matrices with row sums A and column sums B.

fricas

f(A:List PI, B:List PI): FRAC INT == cap(reduce(*, [elementary i for i in A]), reduce(*, [complete i for i in B]))

   Function declaration f : (List(PositiveInteger), List(
      PositiveInteger)) -> Fraction(Integer) has been added to 
      workspace.

Type: Void

For example, there are

fricas

f([2,2,2,2], [2,3,3])

fricas

Compiling function f with type (List(PositiveInteger), List(
      PositiveInteger)) -> Fraction(Integer)

$\label{eq1}12$

(1)

Type: Fraction(Integer)

0-1 matrices whose rows all sum up to two and whose first column has 2 entries equal to one, the others having 3 entries equal to one.