var math/big.karatsubaThreshold

4 uses

	math/big (current package)
		nat.go#L267: var karatsubaThreshold = 40 // computed by calibrate_test.go
		nat.go#L279: 	if n&1 != 0 || n < karatsubaThreshold || n < 2 {
		nat.go#L432: 	if n < karatsubaThreshold {
		nat.go#L445: 	k := karatsubaLen(n, karatsubaThreshold)