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A117100
Numbers n such that nextprime(3*n)>3*nextprime(n) and n is composite (if p is prime then nextprime(p)=p).
0
16, 18, 28, 30, 38, 39, 40, 58, 72, 78, 81, 82, 88, 95, 96, 98, 99, 100, 106, 108, 130, 138, 148, 150, 156, 170, 171, 172, 175, 176, 177, 178, 196, 198
OFFSET
1,1
PROG
(PARI) for(i=1, 200, if(nextprime(3*i)>nextprime(3)*nextprime(i) && !isprime(i), print1(i, ", ")))
CROSSREFS
Sequence in context: A160778 A057369 A178110 * A101848 A032401 A335223
KEYWORD
easy,nonn
AUTHOR
Mohammed Bouayoun (mohammed.bouayoun(AT)sanef.com), Apr 18 2006
STATUS
approved