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Numbers n such that nextprime(3*n)>3*nextprime(n) and n is composite (if p is prime then nextprime(p)=p).
0

%I #3 Jun 29 2008 03:00:00

%S 16,18,28,30,38,39,40,58,72,78,81,82,88,95,96,98,99,100,106,108,130,

%T 138,148,150,156,170,171,172,175,176,177,178,196,198

%N Numbers n such that nextprime(3*n)>3*nextprime(n) and n is composite (if p is prime then nextprime(p)=p).

%o (PARI) for(i=1,200,if(nextprime(3*i)>nextprime(3)*nextprime(i) && !isprime(i),print1(i,",")))

%K easy,nonn

%O 1,1

%A Mohammed Bouayoun (mohammed.bouayoun(AT)sanef.com), Apr 18 2006