The cache is not at the listed coordinates. They are bogus. First, have sum fun with the puzzle then calculate the final coordinates.
To solve the puzzle, place the numbers 1 through 13 in the lettered spaces of the diagram so that the numbers reading from the center circle out to the triangles add up to the totals in those triangles. Each number is used only once.

The cache is a micro located here:
North = ((((H+M)*D+A)*(L^E-F+K^E)*K*C+G)*G^G-G)/(J+E)^I
West = (L^G*(J-E)*(F*E/G*(M+C)*(E*H+K)+H)-A)/B^I*E^G*L
Be sure to follow PEMDAS when evaluating the coordinate formulas. The caret (^) is the exponentiation symbol.
You can check your cache coordinates on GeoChecker.com.
NOTICE: The cache had to be moved to a new location. Once you have calculated and verified the coordinates, they must be corrected. The coordinates of the final location can be found by ADDING 0.491' to the calculated North coordinate and SUBTRACTING 0.017' from the calculated West coordinate.