Fill the grid such that each row, column, and orthogonally-connected 7-cell region contains the digits 1-7 with no repeats. The regions must be determined by the solver. The sum of the digits along a blue line must be the same within each region the line passes through. Eg if r2r3r4c6 were in one region and r5r6c6 were in a separate region, then the sum of the digits in r2r3r4c6 = the sum of the digits in r5r6c6. Adjacent digits on a green line must have a difference of at least 4.