const math/big.MaxBase

4 uses

	math/big (current package)
		natconv.go#L24: const MaxBase = 10 + ('z' - 'a' + 1) + ('Z' - 'A' + 1)
		natconv.go#L111: 		!fracOk && 2 <= base && base <= MaxBase ||
		natconv.go#L198: 				d1 = MaxBase + 1
		natconv.go#L264: 	if base < 2 || base > MaxBase {