Math Is Fun Forum

I have 5 tough puzzles that I've been trying to crack for ages and just can't get the answers, so I'd really appreciate it if someone could help me out. Thanks, Josh.

Number seqeunce 1:

Here's a number sequence:
1, 11, 21, 1211, 111221, 312211...
Find the rule and post the two next numbers in the sequence.

Number seqeunce 2:

Here's a number sequence:
111, 112, 21123, 1312, 2114, 121, 25262, 73123...
Find the rule and post the two next numbers in the sequence.

Number seqeunce 3:

Here's a number sequence:
101010, 1120, 222, 132, 110, ...
Find the rule and post the two next numbers in the sequence.

Number seqeunce 4:

What numbers should be put instead of question marks:
4, 7, 6, 2, 3, 7, 2, ?, ?.

Two Integers:

I'm thinking of two integer numbers, each if them is more than 1 and their sum is less than 100.
I tell my friend Serge the sum of these two numbers, and another friend, Polly, product of these two numbers.
Then such a dialog took place:
P: I can't determine what are these numbers.
S: Ah, i knew you wouldn't be able to do this.
P: Oh, then i know what they are!
S: Oh, then i know them too!

Can you determine the numbers?