You: Seriously?! THAT LONG?!

Meanwhile back in the ranch, great work! A+++++++

]]>- Around 300 bytes
- Optimized for speed (finance variables, precomputes things)
- Takes 320 seconds for 400 digits, runs out of memory on my 84+ when trying to compute more. Could probably run to about 1020 digits on an 84+CE.
- Compatible with the entire TI-83+ family
- I have no idea what a "complicated command" is so I can't say whether this uses any.

The problem with most Pi calculation algorithms is memory requirement— it's a long time since I last looked them up, but IIRC most algorithms' memory requirement is linear in the input. This particular algorithm could be adapted to 2000 digits or so, but that would require constantly archiving and unarchiving lists and slow it down significantly. 2000 digits would take maybe a day.

`ClrHome CLASSIC Prompt N startTmr->T 10->B Repeat M*27L^^2<|E12 B-1->B ~int(~N/B)+1->S //number of batches 10^B->M ~int(~BS/log(13.5))+3->L //2 extra terms for accuracy End Disp "M=10^(",B seq(X,X,0,L->L6 5L6+3->L1 // representation of pi 27(L6^^2+L6)+6->L2 // denominators 2(L6+1)^^2-(L6+1)->L3 // numerators DelVar L6 Disp "INIT TIME",checkTmr(T For(X,0,S-1 ~int(~L+BX/log(13.5))+1->dim(L1 //we only need this many terms L1M->L1 0->FV For([recursiven],dim(L1),1,~1 L1([recursiven])+FV*L3([recursiven]->PV int(PV/L2([recursiven]->FV PV-FVL2([recursiven]->L1([recursiven] End int(PV/M //Disp Ans PV-MAns->L1(1 End Disp "NTH DIGIT = ",int(10fPart(int(PV/M)10^(N-B(S-1)-1 Disp "TIME",checkTmr(T`

Because of that limitation, the program will never be simple, fast for any value over certain N's, and will likely not be under 1000 bytes. Because of that, I am almost inclined to declare this challenge impossible.

Edit: Even if you stored as many digits of pi as are available in the 1000 bytes (978), that still would not be a valid program as it doesn't solve for all n'th digits of pi within the calculators limitations

]]>However, doing some research doesn't hurt.

EDIT: Reread the post and realized that my proposed method wouldn't work.

A guideline for contests like these are to solve it yourself first. That way you know there is at least one way to solve the problem.

]]>- Do something nearly impossible
- Don't use any standard method of doing it
- Keep a very complex task, simple
- Keep it small

- The user must type a real number indicating to find out the -nth digit of Pi
- The program must be simple as possible
- (OPTIONAL) the program can store the previous digits of Pi in a string (Begin string: "3.")
- Do not use the command summation Σ. Or any other complicated commands
- The easier the better
- Make the calculations as fast as possible
- Display the digit in Ans (obviously)
- Make it compatible for
**ALL**graphing calculators (With the Input command and other necessary commands) - ?<1000 bytes (extra credit <460)
- SIMPLE calculations, no formulas