dr san
Well, there probably are several possible ways.
For example:
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00 To 49 can be Low Pairs
50 To 99 can be High Pairs
Pairs that start with Even Digits such as: 01, 28, 49, 66 and 80 can be said to be Even Pairs
Pairs that start with Odd digits can be said to be Odd Pairs.
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Another way:
Pairs that end on 0, 1, 2, 3, and 4 can be Low Pairs, such as 21
Pairs that end on 5, 6, 7, 8, and 9 can be High Pairs, such as 49
Pairs that end with Even Diigts can be said to be Even Pairs, such as 52
Pairs that end with Odd Digits can be said to be Odd Pairs, such as 73
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Same for other filters such as In-Out, Bala-Nced.
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An old regular way was:
LL = Low Low Pairs
HH = High High Pairs
LH = Low High Pairs
HL = High Low Pairs
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EE Even Even Pairs
OO Odd Odd Pairs
EO Even Odd Pairs
OE Odd Even Pairs
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OO Out Out Pairs
II In In Pairs
OI Out In Pairs
IO In Out Pairs
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BB Bala Bala Pairs
NN Nced Nced Pairs
BN Bala Nced Pairs
NB Nced Bala Pairs
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There is also the Low Middle High filter, there are 2 or 3 versions of it, but here I will use this version:
0, 1, 2 = Low
3, 4, 5, 6 = MIddle
7, 8, 9 = High
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I guess that the pairs stuff can also apply to Doubles.
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Another way based on the "10/4":
00 = LELE
47 = LEHO
99 = HOHO
LELE, LELO, LEHE, LEHO
LOLO, LOLE, LOHE. LOHO
HEHE, HELE, HELO, HEHO
HOHO, HOLE, HOLO, HOHE
16 Patterns for Doubles and also for Pairs.
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If you make the 10 X 10 Pairs Grid then you can probably make more stuff
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There are also Sums for the Doubles and for the Pairs:
Lowest Sum = 00
Highest Sum = 18
00 Sum = 00
99 Sum = 18
So there are 19 Sums.
There is more possible stuff based on the Sums.
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We know that there are VTracs and also other like VTracs Patterns, that is patterns similar to VTracs.
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I won't write about every possible thing here.
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I think that maybe I made 10 by 10 pairs grids before as "LANTERN"
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I also wrote about VTracs and VTracs like patterns before maybe as "LANTERN".
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There is also stuff like Skips, Widths and maybe even LDRs for pairs and Doubles.
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Good Luck!
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I think that maybe a very long time ago I made some special filters for pairs, but I never used them nor posted about them, so I forgot about them, I don't even now remember anything about those filters, what I don't post about I forget a lot sooner than the stuff that I post about.
But I didn't dare to post about that stuff at least at that time.