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A089730
Greatest prime factor of all differences prime(n)-q, q prime and q<prime(n); a(1)=0.
0
0, 1, 3, 5, 3, 11, 7, 17, 7, 13, 29, 17, 19, 41, 17, 23, 23, 59, 31, 29, 71, 37, 23, 43, 47, 47, 101, 47, 107, 53, 61, 59, 67, 137, 73, 149, 73, 79, 53, 83, 83, 179, 89, 191, 97, 197, 103, 109, 107, 227, 113, 113, 239, 107, 127, 113, 131, 269, 137, 139, 281, 137
OFFSET
1,3
EXAMPLE
n=10, prime(n)=29: a(10) = Max(Union(Factors(29-prime(i)):i<10)) = Max(Factors(27) u Factors(26) u Factors(24) u Factors(22) u Factors(18) u Factors(16) u Factors(12) u Factors(10) u Factors(6)) = Max({3} u {2,13} u {2,3} u {2,11} u {2,3} u {2} u {2,3} u {2,5} u {2,3}) = Max{2,3,5,11,13} = 13.
CROSSREFS
KEYWORD
nonn
AUTHOR
Reinhard Zumkeller, Jan 07 2004
STATUS
approved