Christmas (2015) is coming!

This year, the front page of will feature an advent calendar. Behind each door, there will be a puzzle with a three digit solution.
As you solve the puzzles, your answers will be stored in a cookie. Behind the door on Christmas Day, there will be a form allowing you to submit your answers. The first person to submit the correct answers will win this array of prizes:
The prizes include an t-shirt, a DVD of Full Frontal Nerdity and a beautiful 2015 winner's medal:
I will be adding to the pile of prizes throughout December.
The next nine people to submit the correct answers will win a winner's medal plus a smaller goody bag of prizes. If less than ten correct entries are submitted, prizes will be given to those with one incorrect answer, then those with two incorrect answers and so on.
Each day's puzzle (and the entry form on Christmas Day) will be available from 5:00am GMT.
To win a prize, you must submit your entry before the start of 2016. Only one entry will be accepted per person. Once ten correct entries have been submitted, I will add a note here and below the calendar. If you have any questions, ask them in the comments below or on Twitter.
So once December is here, get solving! Good luck and have a very merry Christmas!
Edit: The winners and answers can now be found here.

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Comments in green were written by me. Comments in blue were not written by me.
@Anonymous2: Other winners and answers will be available from 1st January
How many wrong answers do I have ? And when will you publish the solutions ?
@Anonymous1: You are (now) correct and on the leaderboard. Well done!
I've submitted my answer! On Christmas too! It's just that I sorta crammed all of the answers today :/

Are you allowed to tell me if I am correct?
I'm so glad for OEIS.

hint hint
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