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Least k such that 1 < p < n < c < k, where p is a prime and c is a composite number such that for every p there exists a distinct c.
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%I #5 Dec 05 2013 19:56:46

%S 3,5,9,9,11,11,15,16,17,17,21,21,23,25,26,26,28,28,31,33,34,34,36,37,

%T 39,40,41,41,45,45,47,49,50,51,52,52,55,56,57,57,59,59,63,64,65,65,67,

%U 69,70,71,73,73,76,77,78,79,81,81,83,83,86,87,88,89,91,91,93,94,95,95

%N Least k such that 1 < p < n < c < k, where p is a prime and c is a composite number such that for every p there exists a distinct c.

%C a(n) is obtained by moving forward beginning with n+1 and counting prime(n) composite numbers, finally adding 1 to the last composite number arising.

%e a(6) = 11 as there are three primes 2,3,5, < 6 and there are three composite numbers 8,9,10 between 6 and 11.

%Y Cf. A092997, A092998, A077154.

%K easy,nonn

%O 2,1

%A _Amarnath Murthy_, Mar 29 2004

%E More terms from Michael Lahm (mpl148(AT)psu.edu), Apr 25 2006