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%I #10 Mar 27 2020 13:04:56
%S 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,
%T 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,
%U 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
%N Largest prime divisors of differences between consecutive primes.
%C If a(n)=2, then corresponding prime-difference is a power of 2.
%C a(n)=2 for twin-prime differences.
%F a(n) = A006530(A001223(n)).
%t Table[FactorInteger[Prime[w+1]-Prime[w]][[ -1, 1]], {w, 2, 256}]
%t FactorInteger[#][[-1,1]]&/@Differences[Prime[Range[2,110]]] (* _Harvey P. Dale_, Sep 24 2017 *)
%o (PARI) a(n) = vecmax(factor(prime(n+1)-prime(n))[, 1]); \\ _Michel Marcus_, Mar 27 2020
%Y Cf. A001223, A006530, A081413, A000230.
%K nonn
%O 2,1
%A _Labos Elemer_, Apr 02 2003
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