import java.io.*
import java.util.*

fun main(args: Array<String>) {
    val sc = Scanner(System.`in`)
    val n = sc.nextInt()
    val array = IntArray(n, { sc.nextInt() }).toMutableList()

    for(s in 1..2) {
        var i = 0
        var k = 0
        var j = array.size - 1

        while (j > 0) {
            array.add(maxOf(array[k + i], array[k + i + 1]))
            i++
            if (i == j) {
                k += i + 1
                i = 0
                j--
            }
        }
    }

    println(array.sum() % 1000000007)
}