PGSS sign for EQUATION

EQUATION
Hold 1st 1st finger hand, back forward and 1st finger pointing inward, and hold 2nd 1st finger hand, back forward and 1st finger pointing inward, one hand's breadth above 1st hand; then move 1st hand downwards one hand's breadth at same time moving 2nd hand upwards one hand's breadth, and return to original position.