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A081412 Largest prime divisors of differences between consecutive primes. 1
2, 2, 2, 2, 2, 2, 2, 3, 2, 3, 2, 2, 2, 3, 3, 2, 3, 2, 2, 3, 2, 3, 2, 2, 2, 2, 2, 2, 7, 2, 3, 2, 5, 2, 3, 3, 2, 3, 3, 2, 5, 2, 2, 2, 3, 3, 2, 2, 2, 3, 2, 5, 3, 3, 3, 2, 3, 2, 2, 5, 7, 2, 2, 2, 7, 3, 5, 2, 2, 3, 2, 3, 3, 2, 3, 2, 2, 2, 5, 2, 5, 2, 3, 2, 3, 2, 2, 2, 2, 3, 2, 2, 2, 2, 3, 3, 2, 3, 3, 5, 3, 3, 2, 3, 5 (list; graph; refs; listen; history; internal format)
OFFSET

2,1

COMMENTS

If a(n)=2, then corresponding prime-difference is a power of 2.

FORMULA

a(n)=A006530[A001223(n)]

EXAMPLE

a(n)=2 for twin-prime differences.

MATHEMATICA

Table[FactorInteger[Prime[w+1]-Prime[w]][[ -1, 1]], {w, 2, 256}]

CROSSREFS

Cf. A001223, A006530, A081413, A000230.

Sequence in context: A147793 A052298 A179938 * A082863 A029411 A165093

Adjacent sequences:  A081409 A081410 A081411 * A081413 A081414 A081415

KEYWORD

nonn

AUTHOR

Labos E. (labos(AT)ana.sote.hu), Apr 02 2003

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Last modified February 14 13:08 EST 2012. Contains 205623 sequences.