```go
package main

import (
	"bufio"
	"fmt"
	"os"
)

type FastReader struct {
	r *bufio.Reader
}

func (fr *FastReader) nextInt() int {
	sign := 1
	val := 0
	c, err := fr.r.ReadByte()
	for (c < '0' || c > '9') && c != '-' {
		c, err = fr.r.ReadByte()
		if err != nil {
			return 0
		}
	}
	if c == '-' {
		sign = -1
		c, _ = fr.r.ReadByte()
	}
	for c >= '0' && c <= '9' {
		val = val*10 + int(c-'0')
		c, err = fr.r.ReadByte()
		if err != nil {
			break
		}
	}
	return sign * val
}

func main() {
	reader := &FastReader{bufio.NewReaderSize(os.Stdin, 1<<20)}
	out := bufio.NewWriterSize(os.Stdout, 1<<20)
	defer out.Flush()

	t := reader.nextInt()
	for ; t > 0; t-- {
		n := reader.nextInt()
		a := make([]int, n)
		G := 0
		for i := 0; i < n; i++ {
			v := reader.nextInt()
			a[i] = v
			G |= v
		}
		if G == 0 {
			fmt.Fprintln(out, 1)
			continue
		}
		prev := make([]int, 20)
		maxgap := make([]int, 20)
		for i := 1; i <= n; i++ {
			x := a[i-1]
			for b := 0; b < 20; b++ {
				if (x>>b)&1 == 1 {
					gap := i - prev[b] - 1
					if gap > maxgap[b] {
						maxgap[b] = gap
					}
					prev[b] = i
				}
			}
		}
		ans := 1
		for b := 0; b < 20; b++ {
			if (G>>b)&1 == 1 {
				gap := n - prev[b]
				if gap > maxgap[b] {
					maxgap[b] = gap
				}
				kb := maxgap[b] + 1
				if kb > ans {
					ans = kb
				}
			}
		}
		fmt.Fprintln(out, ans)
	}
}
```