Question

ladies and gentlemen:

so i was tryina write a program that will solve, or help me identify the 10 ensuing terms of this sequence: 3,7,11,...

i did the arithmetic on paper and i end up with the program below:

[3,7,11,]
T=input("what are the next 10 numbers in the sequence?")
print T

,the user input: map (lambda x : '4x-1' , range(11))

and this was the output:['4x-1', '4x-1', '4x-1', '4x-1', '4x-1', '4x-1', '4x-1', '4x-1', '4x-1', '4x-1', '4x-1']
i danno where did i go wrong, but if you could help, what must i do to get values?, in this format :[15,19,23,...]

Answer 1

...and oh! the program was written in python/pyscripter 2x vision.

Answer 2

you could use a for loop that prints out ten times starting at 15, adding 4 each iteration.

Answer 3

You put your calculation in quotes, which makes it into text.

Answer 4

when i do it without quotes, it gives me an error

Answer 5

it was pretty easy with the for loop, i just thought since map (lambda x:x*x,range(10)) works, that would work too. but how come that works and mine doesn't work?

Answer 6

Well, that error is your issue. So, what is the error for? How the lambda function is being done?

Answer 7

it's an syntax error only when i take the quotes off, and like i said, with the quotes i get ['4x-1', '4x-1', '4x-1', '4x-1', '4x-1', '4x-1', '4x-1', '4x-1', '4x-1', '4x-1', '4x-1']

Answer 8

OK. Syntax error. Well, why not do the lambda on another line so you can see if the syntax is in the lambda or in the map.

Answer 9

using the for loop, say i want the program to tell for every single number in the sequence whether it's even or odd, how do i do that? because what i did was :

for i in range(3,14):
X = 4*i -1
print x
if x%2 == 0:
print x, "is even"
else:
print x, "is odd"

Answer 10

I can't say I know the Python syntax to help you.. but in java you would start i out where you want to start testing, and have the boolean expression make the loop end whenever you want.. and for each iteration test for even/odd with the modulus operator- which it seems you already have that part; like

```
for(int i = 3; i <= 14; i++) {
if(i%2 == 0)
System.out.println(i + " Is even.");
else
System.out.println(i + " Is odd.");
}
```

Answer 11

java ^

Answer 12

Just remember to define x outside the loop or it can not be used outside the loop.

Answer 13

and how do i exactly define x outside the loop?

Answer 14

In a strongly typed language with hard declarations it would be something like:
int x

In Python, which uses adaptive typing, you would do something like:
x=0

Then it exists before the loop.

Hmmm.... but looking at that code, I am not sure if you want to be out of the loop or not. It seems you may have a formatting problem caused by not using the code highlighting system.

Did you mean this:
```
for i in range(3,14):
x = 4*i -1
print x
if x%2 == 0:
print x, "is even"
else:
print x, "is odd"
```
or this:
```
for i in range(3,14):
x = 4*i -1
print x
if x%2 == 0:
print x, "is even"
else:
print x, "is odd"
```
By putting ``` (the key with the ~ on it) on a separate line above and below the code, it keeps formatting and does code highlighting.