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A039639 Fixed point of "k -> k/2 or (k-1)/2 until result is prime", starting with prime(n)+1.

%I A039639 #13 Aug 08 2025 03:18:00
%S A039639 3,2,3,2,3,7,2,5,3,7,2,19,5,11,3,13,7,31,17,2,37,5,5,11,3,3,13,13,13,
%T A039639 7,2,2,17,17,37,19,79,41,5,43,11,11,3,97,3,3,53,7,7,7,29,7,7,31,2,2,
%U A039639 67,17,139,17,71,73,19,19,157,79,83,5,43,43,11,11,23,23,47,3,97,199,3
%N A039639 Fixed point of "k -> k/2 or (k-1)/2 until result is prime", starting with prime(n)+1.
%H A039639 Reinhard Zumkeller, <a href="/A039639/b039639.txt">Table of n, a(n) for n = 1..10000</a>
%t A039639 (* See A039634. *)
%o A039639 (Haskell)
%o A039639 a039639 = until ((== 1) . a010051) (flip div 2) . (+ 1) . a000040
%o A039639 -- _Reinhard Zumkeller_, Nov 17 2013
%Y A039639 Cf. A039634-A039645.
%Y A039639 Cf. A010051, A000040, A039643, A039641, A039634.
%K A039639 nonn
%O A039639 1,1
%A A039639 _Wouter Meeussen_
%E A039639 Offset corrected by _Reinhard Zumkeller_, Nov 17 2013