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A076559 Greatest prime divisor of n-th interprime: (prime(n) + prime(n+1))/2.

%I A076559 #12 May 10 2023 08:31:04
%S A076559 2,3,3,3,5,3,7,13,5,17,13,7,5,5,7,5,2,23,3,19,3,43,31,11,17,7,3,37,5,
%T A076559 43,67,23,3,5,11,5,11,17,11,5,31,3,13,11,41,31,5,19,11,59,5,41,127,13,
%U A076559 19,5,137,31,47,3,5,103,13,7,3,167,19,29,13,89,11,37,47,127,193,131,19
%N A076559 Greatest prime divisor of n-th interprime: (prime(n) + prime(n+1))/2.
%H A076559 Amiram Eldar, <a href="/A076559/b076559.txt">Table of n, a(n) for n = 2..10000</a>
%F A076559 a(n) = A006530(A024675(n-1)). - _R. J. Mathar_, May 10 2023
%p A076559 A076559 := proc(n)
%p A076559     A006530((ithprime(n)+ithprime(n+1))/2) ;
%p A076559 end proc:
%p A076559 seq(A076559(n),n=2..120) ;  # _R. J. Mathar_, May 10 2023
%t A076559 gpf[n_] := FactorInteger[n][[-1, 1]]; p = Select[Range[405], PrimeQ]; gpf /@ ((p[[2 ;; -2]] + p[[3 ;; -1]])/2) (* _Amiram Eldar_, Aug 29 2019 *)
%Y A076559 Cf. A071216.
%K A076559 easy,nonn
%O A076559 2,1
%A A076559 _Zak Seidov_, Oct 19 2002