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#include <cstdio>
#include <cmath>

const unsigned MAX = 300000;
const unsigned PPP = 1000000007;

int n;
unsigned nums[MAX];

unsigned getSum(int i, int j) {
    if(i == 0) return nums[j];
    --i;
    unsigned s = nums[j] < nums[i] ? nums[j] + PPP : nums[j];
    unsigned diff = s - nums[i];
    unsigned ret = s - diff;
    return ret;
}

void countRanges(int start, int len, unsigned *ret) {
    if (start + len == n) {
        unsigned sum = getSum(start, n) % PPP;
        if ((sum & 1) == 0) {
            ++(*ret);
            if (*ret > PPP) *ret -= PPP;
        }
        return;
    }
    unsigned sum = getSum(start, len + start) % PPP;
    if ((sum & 1) == 1) {
        return;
    }
    for (int i = 1; i < (n - start - len + 1); ++i) {
        countRanges(start+len, i, ret);
    }
}

int main() {
    scanf("%d", &n);
    unsigned sum = 0;
    for (int i = 0; i < n; ++i) {
        unsigned num;
        scanf("%u", &num);
        sum += num;
        if (sum >= PPP) sum -= PPP;
        nums[i] = sum;
    }
    unsigned ret = 0;
    for(int i = 1; i <= n; ++i) {
        countRanges(0, i, &ret);
    }
    printf("%d\n", ret);
    return 0;
}