FUNCTION : findtype2 - find type 2 identities
CALLING SEQUENCE : findtype2(T)
PARAMETERS : T - positive integer
-
GLOBAL VARIABLES :
xprint,NEWJACID,RJID,SYMJID,
TT1,TT2,PROVEDFL1,EBL
SYNOPSIS :
Before running the functions G,H,GM,HM,GE,HE must be defined.
findtype2(T) cycles through symbolic expressions
_G(a) _G(b) + c _H(a)_H(b)
where 2 ≤ n ≤ T, ab=n, (a,b)=1, b < a, c in {-1,1}, and
(*) GE(a) + GE(b) - (HE(a) + HE(b)) in Z
using CHECKRAMIDF to check whether the expression corresponds to a
likely eta-product.
If proveit is true then provemodfuncidBATCH (from theataids
package) is used to prove it. Condition (*) eliminates the case of fractional
powers of q. The procedure also returns a list of [a,b,c] which
give identities.
NOTE: Output should be assigned myramtype2.
EXAMPLES :
> wit(qseries):
> with(thetaids):
> with(ramarobinsids):
> xprint:=false: proveit:=true:
> G:=j->1/GetaL([1],10,j):H:=j->1/GetaL([3],10,j):
> GM:=j->1/MGetaL([1],10,j): HM:=j->1/MGetaL([3],10,j):
> GE:=j->-GetaLEXP([1],10,j):HE:=j->-GetaLEXP([3],10,j):
> myramtype2:=findtype2(6);
*** There were NO errors. Each term was modular function on
Gamma1(60). Also -mintotord=40. To prove the identity
we need to check up to O(q^(42)).
To be on the safe side we check up to O(q^(160)).
*** The identity below is PROVED!
[2, 3, -1]
_G(2) _G(3) - _H(2) _H(3) =
3
eta(15 tau) eta(12 tau) eta(10 tau) eta(4 tau)
-----------------------------------------------
2 2
eta(30 tau) eta(20 tau) eta(5 tau) eta(2 tau)
[[2, 3, -1]]
DISCUSSION :
For G,H defined G(2) G(3) - H(2) H(3) is an eta-product and
the identity is proved.
SEE ALSO :
findtype1, findtype2,
findtype3, findtype4,
findtype5, findtype6,
findtype7, findtype8,
findtype9, findtype10