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Run lengths in A251539.
3

%I #11 Aug 01 2018 10:54:19

%S 7,1,10,1,10,1,10,1,10,1,10,4,1,8,1,10,1,10,1,10,1,10,1,10,1,10,2,10,

%T 1,10,1,10,1,10,1,10,1,10,1,10,2,10,1,10,1,10,1,10,1,10,1,10,1,10,3,1,

%U 8,1,10,1,10,1,10,1,10,1,10,1,10,2,10,1,10,1,10

%N Run lengths in A251539.

%H Reinhard Zumkeller, <a href="/A251768/b251768.txt">Table of n, a(n) for n = 1..10000</a>

%t max = 2000 (* = max term of A251538 *);

%t A098548 = {1, 2, 3};

%t For[n = 4, n <= 8 max, n++, If[GCD[n, A098548[[-1]]] == 1 && GCD[n, A098548[[-2]]] > 1, AppendTo[A098548, n]]];

%t A251538 = Select[Range[max], A098548[[2 # + 3]] > A098548[[2 # + 1]] + 6&];

%t A251539 = Differences[A251538];

%t Length /@ Split[A251539] (* _Jean-François Alcover_, Aug 01 2018 *)

%o (Haskell)

%o import Data.List (group)

%o a251768 n = a251768_list !! (n-1)

%o a251768_list = map length $ group a251539_list

%Y Cf. A249943, A251767.

%K nonn

%O 1,1

%A _Reinhard Zumkeller_, Dec 08 2014