The arrows certainly seem to have meaning that must somehow be provided for the braille reader. I think the straight horizontal arrows denote an addition number family, and, possibly, the up and right arrows denote a multiplication number family.
Tactile representation would preserve the print's focus on presenting the numbers with spatial relationships.
Still, I think a well worded TN and shapes designated specifically for each kind of number family arrow could get the information to the reader. This might be particularly important if it saves you from inserting scores or hundreds of tactiles. If you use shapes, I suggest that they should be created using Nemeth rules for representing a new shape, and the numbers (including numbers represented by letters) that are part of these families should be in the Nemeth bubble with the shape.