Question 1123852
i count 16


actually 18, but 2 of them are duplicates, so 16 unique.


i checked 3000 times so i'm pretty sure the count is accurate.


here's my worksheet.


<img src = "http://theo.x10hosting.com/2018/092103.jpg" alt="$$$" >


first i looked at the ones that started with 3 heads.
then i looked at the ones that ended with 3 heads.
then i looked at the ones that started with 2 heads.
then i looked at the ones that ended with 2 heads.
then i looked at the ones that started with 1 head.
then i looked at the ones that ended with 1 head.


the spreadsheet is organized in that manner.
the ones in red were the duplicates.
i did an eyeball scan and i also gave each set a numeric code.
if the codes was the same, those were duplicates, as confirmed by an eyeball check.


if i were you, i would go with 16.
hopefully that will do the trick.