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A092996
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.
3
3, 5, 9, 9, 11, 11, 15, 16, 17, 17, 21, 21, 23, 25, 26, 26, 28, 28, 31, 33, 34, 34, 36, 37, 39, 40, 41, 41, 45, 45, 47, 49, 50, 51, 52, 52, 55, 56, 57, 57, 59, 59, 63, 64, 65, 65, 67, 69, 70, 71, 73, 73, 76, 77, 78, 79, 81, 81, 83, 83, 86, 87, 88, 89, 91, 91, 93, 94, 95, 95
OFFSET
2,1
COMMENTS
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.
EXAMPLE
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.
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Amarnath Murthy, Mar 29 2004
EXTENSIONS
More terms from Michael Lahm (mpl148(AT)psu.edu), Apr 25 2006
STATUS
approved