func NewSequence(width int, numPeriods int) Sequence {
	return make(Sequence, Width64bits+numPeriods*width)
}
NewSequence allocates a new Sequence that holds the given number of periods
with accumulator states of the given width.
package encoding
import (
	"fmt"
	"math"
	"time"
	"github.com/getlantern/goexpr"
	"github.com/getlantern/golog"
	"github.com/getlantern/zenodb/expr"
)
var (
	log = golog.LoggerFor("zenodb.encoding")
)
type Sequence []byte