human
Sum of the series 1 , 2 , 4 , 3 , 5 , 7 , 9 , 6 , 8 , 10 , 11 , 13. . till N | Function to find the sum of first N odd numbers.
Function to find the sum of first N even numbers.
Function to overall find the sum of series.
Initial odd numbers.
Initial even numbers.
First power of 2.
Check for parity for odd / even.
Counts the sum.
Get the minimum out of remaining num or power of 2.
Decrease that much numbers from num.
If the segment has odd numbers.
Summate the odd numbers By exclusion.
Increase number of odd numbers.
If the segment has even numbers.
Summate the even numbers By exclusion.
Increase number of even numbers.
Next set of numbers.
Change parity for odd / even.
Driver code"
Solution in Python:

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What is a code to sum of the series 1 , 2 , 4 , 3 , 5 , 7 , 9 , 6 , 8 , 10 , 11 , 13?
assistant
#Here is code to sum of the series 1 , 2 , 4 , 3 , 5 , 7 , 9 , 6 , 8 , 10 , 11 , 13.
 def sumodd ( n ) :
	return ( n * n )
def sumeven ( n ) :
	return ( n * ( n + 1 ) )
def findSum ( num ) :
	sumo = 0
	sume = 0
	x = 1
	cur = 0
	ans = 0
	while ( num > 0 ) :
		inc = min ( x , num )
		num -= inc
		if ( cur == 0 ) :
			ans = ans + sumodd ( sumo + inc ) - sumodd ( sumo )
			sumo += inc
		else :
			ans = ans + sumeven ( sume + inc ) - sumeven ( sume )
			sume += inc
		x *= 2
		cur ^= 1
	return ans
n = 4
print ( findSum ( n ) )