Question: Equations are acting inert

I have a matrix and generate difference tables from it's diagonals. Works fine. Then I make a polynomial from the first row of the difference table. I have three polynomials. They are all acting inert, just will not evaluate.

I cannot see what the problem is.
 

restart

interface(rtablesize = 12)

[10, 10]

i) Recurrence relation

 

"Recurrence Relation for next column. . The matrix starts at 1,1 not 0,0 A(i,j)=A(i-1,j-1)*(j-2)+A(i,j-1)"
``

NULL``

Msize := 12

A := Matrix(Msize)

A[1, 1] := 1

1

for i from 2 to Msize do for j from i to Msize do A[i, j] := A[i, j-1]*(j-2)+A[i-1, j-1] end do end do

A

Matrix(%id = 36893489695842121836)

``

``

viia)  General formula for diagonals:-

Select diagonal  & Difference Table procedures

 

diag := proc (M::Matrix, dg::posint) local i, rd, c, dt; rd := LinearAlgebra:-RowDimension(M); dt := Matrix(rd, rd); for i from dg to rd do dt[1+i-dg, 1] := M[1+i-dg, i] end do; return dt end proc

proc (M::Matrix, dg::posint) local i, rd, c, dt; rd := LinearAlgebra:-RowDimension(M); dt := Matrix(rd, rd); for i from dg to rd do dt[1+i-dg, 1] := M[1+i-dg, i] end do; return dt end proc

diag(A, 5)

Matrix(%id = 36893489695866397388)

diftab := proc (M::Matrix) local i, j, cl, rd; rd := LinearAlgebra:-RowDimension(M); for i from rd by -1 to 1 do if M[i, 1] = 0 then rd := rd-1 else break end if end do; cl := rd; for i from 2 to cl do for j to rd-i do M[j, i] := M[j+1, i-1]-M[j, i-1] end do end do; print(M); return M end proc

proc (M::Matrix) local i, j, cl, rd; rd := LinearAlgebra:-RowDimension(M); for i from rd by -1 to 1 do if M[i, 1] = 0 then rd := rd-1 else break end if end do; cl := rd; for i from 2 to cl do for j to rd-i do M[j, i] := M[j+1, i-1]-M[j, i-1] end do end do; print(M); return M end proc

diftab(diag(A, 4))

Matrix(%id = 36893489695866348116)

gnrpoly := proc (M::Matrix) local i, p, rd, n; rd := LinearAlgebra:-RowDimension(M); for i from rd by -1 to 1 do if M[1, i] = 0 then rd := rd-1 else break end if end do; p := 0; for i from 0 to rd-1 do p := p+M[1, i+1]*binomial(n, i) end do; return p end proc

proc (M::Matrix) local i, p, rd, n; rd := LinearAlgebra:-RowDimension(M); for i from rd by -1 to 1 do if M[1, i] = 0 then rd := rd-1 else break end if end do; p := 0; for i from 0 to rd-1 do p := p+M[1, i+1]*binomial(n, i) end do; return p end proc

"for i from 0 to 3 do print("Diagonal  ",i);   eqn:=gnrpoly(diftab(diag(A,i+1)));    cat(poly,i):=unapply(factor(expand(eqn)),n);    print("--------------------------------------------------------------");  end do"

"--------------------------------------------------------------"

NULL

``

``

The equations do not evaluate. They are acting inert

poly1(n)

(1/2)*n*(1+n)

poly1(2)

(1/2)*n*(1+n)

poly2(n)

(1/24)*n*(3*n+5)*(n+2)*(n+1)

poly2(3)

(1/24)*n*(3*n+5)*(n+2)*(n+1)

poly3(n)

(1/48)*n*(n+1)*(n+3)^2*(n+2)^2

poly3(-1)

(1/48)*n*(n+1)*(n+3)^2*(n+2)^2

eqn

6*n+38*binomial(n, 2)+93*binomial(n, 3)+111*binomial(n, 4)+65*binomial(n, 5)+15*binomial(n, 6)

value(eval(eqn, n = 4))

6*n+38*binomial(n, 2)+93*binomial(n, 3)+111*binomial(n, 4)+65*binomial(n, 5)+15*binomial(n, 6)

eqn1 := expand(eqn)

(3/4)*n+2*n^2+(97/48)*n^3+(47/48)*n^4+(11/48)*n^5+(1/48)*n^6

eval(eqn1, [n = 4])

(3/4)*n+2*n^2+(97/48)*n^3+(47/48)*n^4+(11/48)*n^5+(1/48)*n^6

NULL


 

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