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1) COOLnumbers are the sequence 1, 1, 2, 3, 5, 8, 13, 21, 34 … As you can (probably) see, each COOL number is the sum of the previous two. ugly numbers, on the other hand, are the sum of the previous three.
a. Find the 19th and 119th ugly numbers.
b. Use “bar” to give a bar plot of the first 10 ugly numbers. Label your axes.
c. Plot the first 100 ugly numbers on a logarithmic y-scale. Do you notice anything? What might it mean?
Can anyone help me make this script for matlab?
We need the first three "ugly numbers" before we can start.Quote:
Originally Posted by Mathhelpz
CB
alright ill get back to you,
could you put like what general matlab script i need to know? Like how would i find the nth term, using bar, and then plotting?
The first 100 will be produced by:Quote:
Originally Posted by Mathhelpz
or you could solve the recurrence and code the solution as a function of nCode:TriNacci=zeros(1:100);
TriNacci(1:3)=[1,1,2]; %put the three initial values here
for idx=4:100
TriNacci(idx)=TriNacci(idx-3)+TriNacci(idx-2)+TriNacci(idx-1);
end
CB
can you check if this is correct??
for n=1:119
phi=(1+sqrt(5))*(1/2);
F=((phi^n)-(1-phi)^n)/sqrt(5);
bar(1:10 ,F)
xlabel('numbers')
ylabel('range')
semilogy(1:100 ,F)
end;
I would say that
"
u(1)=1;
u(2)=1;
for kk=3:100;
u(kk)=u(kk-1)+u(kk-2);
end
"
would do the trick. Looking to u on a logaritmic Yscale you see a straight line. This indicates that u is some kind of logaritmic function.
Check what? These are the Fibonacci numbers (your so called COOL numbers) not your UGLY numbers.Quote:
Originally Posted by Mathhelpz
CB
These are also the COOL-Fibonacci numbers.Quote:
Originally Posted by Jeroentje
CB
Thanks for the help !
"
u(1)=1;
u(2)=1;
u(3)=2;
for kk=4:100;
u(kk)=u(kk-1)+u(kk-2)+u(kk-3);
end
"
Which has already been posted in message #4 in this thread (only with better syntax)Quote:
Originally Posted by Jeroentje
CB
i need help doing the bar plot....
u(1)=0;
u(2)=1;
u(3)=1;
for kk=4:119;
u(kk)=u(kk-1)+u(kk-2)+u(kk-3);
end
Find1 = u(19);
Find2 = u(119);
That's the program and it works for what i want to find.
How to I do the bar plot part..
* a. Use “bar” to give a bar plot of the first 10 ugly numbers. Label your axes.*
I Tried doing like bar (range(1:10))*u or something but that doens't seem right... Hope you can help
bar(u(1:10));Quote:
Originally Posted by Mathhelpz
CB