Monday, June 29, 2009

Thomanujan Number - 1229

INVALID POST
Thanks to Jeswin for pointing out bug in code.
:S :( Sheepish smile

1 comment:

Thomas Jay Cubb said...

Just made a discovery!

For a problem on a sample space of cardinality up to 1229, it is possible to encode the information inside a 4-byte integer.

We can do it with prime number multiplication - the product is uniquely decomposable as everybody knows. The product of the first 1229 prime numbers fits within MAXINT!!!

The possibilities are endless....

- sonofdelphi


Absurd numerological coincidence :)
* Discovery made on 6/29. If 12/29 is divided by 6/29, the result is 2/1 !!!

Logical end of

Bus-Routes

Looking for a function

Code used to make the discovery
Hardly optimal. Stolen from the web and modified.

#include stdio.h
#include iostream
#include vector

using namespace std;
vector int anPrimes;

#define LIMIT 10000

void main()
{
int n=LIMIT,i=1,j,c;
unsigned int nProduct=1;
unsigned int nPrimeCount=0;
unsigned int nLastPrime = 0;
unsigned int nLastProduct = 0;

while(i<=n)
{
c=0;
for(j=1;j<=i;j++)
{
if(i%j==0)
c++;
}

if(c==2)
{
nProduct *= i;
if(nProduct > UINT_MAX)
break;

nPrimeCount++;
nLastPrime = i;
nLastProduct = nProduct;

}
i++;
}

cout "Last Prime : " nLastPrime endl;
cout "Prime Cardinal: " nPrimeCount endl;
cout "Product : " nProduct endl;
cout "MAXINT : " UINT_MAX endl;

getchar();
}

OUTPUT

Last Prime : 9973
Prime Cardinal: 1229
Product : 3975369062
MAXINT : 4294967295