maximum_subseq_sum.py

def maxSumWO3Consec(arr,n):
    sum = [0 for k in range(n)]

    if n >= 1:
        sum[0] = arr[0]
    if n >= 2:
        sum[1] = arr[0] + arr[1]
    if n > 2:
        sum[2] = max(sum[1],max(arr[1] + arr[2], arr[0] + arr[2]))
    
    for i in range(3,n):
        sum[i] = max(max(sum[i-1],sum[i-2]+arr[i]),arr[i] + arr[i-1] + sum[i-3])

    return sum[n-1]

arr = [100,1000,100,1000,5]
n = len(arr)
print(maxSumWO3Consec(arr,n))