var math/big.karatsubaSqrThreshold

4 uses

	math/big (current package)
		nat.go#L516: 	if n&1 != 0 || n < karatsubaSqrThreshold || n < 2 {
		nat.go#L548: var karatsubaSqrThreshold = 260 // computed by calibrate_test.go
		nat.go#L572: 	if n < karatsubaSqrThreshold {
		nat.go#L583: 	k := karatsubaLen(n, karatsubaSqrThreshold)