A251768 - OEIS

A251768

Run lengths in A251539.

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, 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, 8, 1, 10, 1, 10, 1, 10, 1, 10, 1, 10, 1, 10, 2, 10, 1, 10, 1, 10

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,1

LINKS

Reinhard Zumkeller, Table of n, a(n) for n = 1..10000

MATHEMATICA

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

A098548 = {1, 2, 3};

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

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

A251539 = Differences[A251538];

Length /@ Split[A251539] (* Jean-François Alcover, Aug 01 2018 *)