This symbol is called a Triskele and is
often reffered to as a the three-legged Swastika.
It was aopted
by the Nazi's and is used as the flag of the
Afrikaner Weerstandbeweging (AWB) in South Africa.
sevens which are the supposed numerical value of YAHWEH
(or God in
Abrahamic religion) and opposed to the anti-christ number of 666.
777 represents the anti-anti-christ.