%I
%S 1,6,8,9,14,15,18,20,21,24,25,26,30,32,33,34,35,36,38,39,44,48,49,50,
%T 51,54,55,56,62,63,64,65,68,69,74,75,76,77,78,80,81,84,85,86,90,91,92,
%U 93,94,95,96,98,99,104,105,110,111,114,115,116,117,118,119,120,121,122,123
%N Numbers n such that nextprime(2*n)<2*nextprime(n) (if p is prime then nextprime(p)=p).
%C if p is prime and nextprime(p*n)<nextprime(p)*nextprime(n) then n is composite
%e nextprime(2*6)=13 and nextprime(2)*nextprime(6)=2*7=14 then 6 is member because 13<14
%o (PARI) for(i=1,150,if(nextprime(2*i)<nextprime(2)*nextprime(i),print1(i,",")))
%K easy,nonn
%O 1,2
%A Mohammed Bouayoun (mohammed.bouayoun(AT)sanef.com), Apr 18 2006
