I am crazy

Yesterday, I see this about Pi:

We learn that we can start to write down Pi (π) = 3.141592653589….. but that we can never finish it. Pi (π) goes on forever and has no repeating pattern to its digits – it is what is called an irrational number. In fact if you search long enough within the digits of Pi (π) you can [find any number, including your birthday.]

So i want to know at which digit, my birthday was appearing in the list of digits of Pi (only the first time: because if it is infinite, the sequence will certainly repeat further!!!

How i can calculate the digits of Pi to see it ?

  1. I need big number library

  2. A formula to calculate Pi
    a) π = (4/1) - (4/3) + (4/5) - (4/7) + (4/9) - (4/11) + (4/13) - (4/15) ...
    b) π = 3 + 4/(234) - 4/(456) + 4/(678) - 4/(8910) + 4/(101112) - 4/(121314) ...
    c) sinus(180/aVeriBigNumber)
    d) π = 2 * (Arcsin(sqrt(1 - x^2)) + abs(Arcsin(x))) (where x is a number between -1 and 1)

Who want teach me the bignum library ?

How many week to know at which digit my birthday is ?

Does \pi contain all possible number combinations? - Mathematics Stack Exchange

We can also search for a name !

According to Mathematica, when ππ is expressed in base 128 (whose digits can therefore be interpreted as ASCII characters),

  • "NO" appears at position 702;
  • "Yes" appears at position 303351.

Given (following Feynman in his Lectures on Physics) that any question AA with possible answer A′A′ (correct or not) can be re-expressed in the form "Is A′A′ a correct answer to AA?", and that such questions have either "no" or "yes" answers, this proves the second sentence of the claim--and shows just how empty an assertion it is. (As others have remarked, the first sentence--depending on its interpretation--is either wrong or has unknown truth value.)

With javascript:

No, that's not necessarily true. Let's say you were born March 13. Consider the number


where the first four digits after the decimal point are 13-03 (not 03/13 because you're French :~) ) and then comes
one zero
one one
two zeros
one one
three zeros
one one
four zeros
one one
five zeros
one one
... and so on forever.

The sequence of digits goes on forever; it doesn't consist of the same digits repeated, like 0.123123123123..., so it's irrational. And your birthday doesn't occur more than once.

(Please don't tell us what your actual birthdate is.)

Pi, however, is special; not only is it irrational, like most numbers, but it's also believed to be normal, which means that every sequence of N digits occurs as often as every other sequence of N digits. That's what the paragraph you cited is saying. So in π, specifically, yes, you'll probably find your birthday infinitely many times.

Nothing to it. You just do Untitled script pic and then you do arithmetic as usual.

But what you really need to learn is more complicated than that. The bignum library gives you exact large integers, and exact rationals, but it can't give you exact reals, and the problem you're trying to solve involves the digits of the decimal expansion of a real number. There actually are arithmetic packages that would give you arbitrary precision real numbers (but of course not infinite precision), but not in Snap!. So what you'd have to do is this:

  1. Pick one of your formulas, say (2a) in your list.
  2. Add the first thousand terms using exact rational arithmetic.
  3. Convert the result to a long decimal fraction not by doing arithmetic on it (which would eliminate all but ≈15½ digits of precision) but by manipulating it as text.
  4. If your birthday is in the result, you're done.
  5. If not, go back to step 2, but add the first ten thousand terms. Etc.

I always tell my students that there are two kinds of programming that they should never try to do themselves, but should instead hire an expert. One is security; the other is arithmetic on real numbers. If you do it yourself, you'll probably get an answer, but the answer will almost certainly be wrong.

Is this helping him with his project, or is this showing off that you looked it up? Come on, be helpful.

I'm not French, i speak french...

I know, but for me, it's not a problem... I was born at the start of the term of 5th Chancellor of your university (AHB)

Isn't that 1885, the start of the term of Edward Singleton Holden?
You should probably calculate Pi to a certain number of digits, turn it into a string and look for the number, and keep going if you can't find it.

They're Canadian.

The problem is: When does one know-when a digit is a final digit, more calculating, more accurately we win, so if we gain in precision is that the result changes ... How much it takes cycles to know if a number will not change anymore ... ex: 3.141 never change after x cycles so we can look into to see if this string contain what we want to find

1303 : 98 times × in the first 1000000 decimals digits of pi (https://www.dcode.fr/pi-digits)

if you add the year to the search sequence, you probaly not find it...(in the first million...) (In 2020, they managed to calculate Pi at 50 trillion (50,000,000,000,000,000,000) digits (i don't know if the first digit (3) is include or not ... :wink: )

Paren mismatch D:

That's better

Sigh. If you can look that up, so can anyone else.

I know...


loucheman's avatar


Il y a 1 décennie (1 decade ago)
I can't find anything older, sorry

Gamemaker: nostalgia


How i can implant this ?

let i = 1n;
let x = 3n * (10n ** 1000020n);
let pi = x;
while (x > 0) {
x = x * i / ((i + 1n) * 4n);
pi += x / (i + 2n);
i += 2n;
console.log(pi / (10n ** 20n));

thank's a lot

Is there any way this algorithm could be implemented in Snap!?

probably, but it would be very slow.

Indeed, when i active bignums, it run very slow