A089730 Greatest prime factor of all differences prime(n)-q, q prime and q<prime(n); a(1)=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

Links

Table of n, a(n) for n=1..62.

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

Cf. A000040, A030173, A006530.

Sequence in context: A336863 A205708 A309392 * A351368 A105445 A345014

Adjacent sequences: A089727 A089728 A089729 * A089731 A089732 A089733

Keyword

nonn

Author

Reinhard Zumkeller, Jan 07 2004

Status

approved