import java.io.IOException;
import java.io.InputStream;
import java.util.*;

public class Main {

    public static void main(String[] args) {
        // input
        FastScanner sc = new FastScanner();

        int q = sc.nextInt();

        // 合成数か
        boolean[] even = new boolean[100001];

        for (int i = 2; i <= 100000; i++) {
            // 判定済みなのでスキップ
            if (even[i]) {
                continue;
            }
            // 合成を全部埋める
            for (int j = 2; j <= 50000; j++) {
                int v = j * i;
                if (v > 100000) {
                    break;
                } else {
                    even[v] = true;
                }
            }
        }

        int[] count =  new int[100001];
        int lastIndex = 0;
        int ans = 0;

        // 集計
        for (int i = 3; i <= 100000; i += 2) {
            // 条件を満たすなら
            if (!even[i] && !even[(i + 1) / 2]) {
                Arrays.fill(count, lastIndex, i, ans++);
                lastIndex = i;
            }
        }
        Arrays.fill(count, lastIndex, 100000, ans);

        // 入出力
        for (int i = 0; i < q; i++) {
            System.out.println(- count[sc.nextInt() - 1] + count[sc.nextInt()]);
        }
    }

    private static class FastScanner {
        private final InputStream in = System.in;
        private final byte[] buffer = new byte[1024];
        private int ptr = 0;
        private int buflen = 0;

        private boolean hasNextByte() {
            if (ptr < buflen) {
                return true;
            } else {
                ptr = 0;
                try {
                    buflen = in.read(buffer);
                } catch (IOException e) {
                    e.printStackTrace();
                }
                if (buflen <= 0) {
                    return false;
                }
            }
            return true;
        }

        private int readByte() {
            if (hasNextByte()) return buffer[ptr++];
            else return -1;
        }

        private static boolean isPrintableChar(int c) {
            return 33 <= c && c <= 126;
        }

        public boolean hasNext() {
            while (hasNextByte() && !isPrintableChar(buffer[ptr])) ptr++;
            return hasNextByte();
        }

        public String next() {
            if (!hasNext()) throw new NoSuchElementException();
            StringBuilder sb = new StringBuilder();
            int b = readByte();
            while (isPrintableChar(b)) {
                sb.appendCodePoint(b);
                b = readByte();
            }
            return sb.toString();
        }

        public long nextLong() {
            if (!hasNext()) throw new NoSuchElementException();
            long n = 0;
            boolean minus = false;
            int b = readByte();
            if (b == '-') {
                minus = true;
                b = readByte();
            }
            if (b < '0' || '9' < b) {
                throw new NumberFormatException();
            }
            while (true) {
                if ('0' <= b && b <= '9') {
                    n *= 10;
                    n += b - '0';
                } else if (b == -1 || !isPrintableChar(b)) {
                    return minus ? -n : n;
                } else {
                    throw new NumberFormatException();
                }
                b = readByte();
            }
        }

        public int nextInt() {
            long nl = nextLong();
            if (nl < Integer.MIN_VALUE || nl > Integer.MAX_VALUE) throw new NumberFormatException();
            return (int) nl;
        }
    }
}

Measured memory_bytes: 39464