Is the below formula is correct for designing 3 legged 3 ph inductors

L=(0.4x3.14xNsquaredxAcx10exp-8)/(lg+MPL/um)

Modified formula to accommodate fringing flux F and neglecting the
term MPL/um

L=(0.4x3.14xNsquaredxAcxFx10exp-8)/lg

lg =gap length in cm Ac=stackxtongue in cm squared fringing flux F={1+lg/sqrootAc *ln(2G/lg)} and G is the winding length

How to calculate the the actual voltage across the inductor when you have harmonics?

L=(0.4x3.14xNsquaredxAcx10exp-8)/(lg+MPL/um)

Modified formula to accommodate fringing flux F and neglecting the

L=(0.4x3.14xNsquaredxAcxFx10exp-8)/lg

lg =gap length in cm Ac=stackxtongue in cm squared fringing flux F={1+lg/sqrootAc *ln(2G/lg)} and G is the winding length

How to calculate the the actual voltage across the inductor when you have harmonics?