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%I #13 Aug 20 2017 10:56:02
%S 0,2,2,2,2,3,2,2,2,3,2,4,2,3,3,2,2,3,2,4,3,3,2,4,2,3,2,4,2,5,2,2,3,3,
%T 3,4,2,3,3,5,2,5,2,4,4,3,2,4,2,3,3,4,2,3,3,5,3,3,2,6,2,3,4,2,3,5,2,4,
%U 3,5,2,6,2,3,3,4,3,5,2,5,2,3,2,7,3,3,3,4,2,7,3,4,3,3,3,4,2,3,4,4,2,5,2,4,5
%N a(n) is the number of divisors of n that are each coprime to the previous or the following divisor of n.
%H Diana Mecum, <a href="/A136164/b136164.txt">Table of n, a(n) for n = 1..1000</a>
%e The divisors of 28 are 1,2,4,7,14,28. Among adjacent pairs of divisors, 1 and 2 are coprime and 4 and 7 are coprime. Therefore there are a(28) = 4 divisors (1,2,4,7) that are each next to another divisor that they are coprime to.
%t Table[Boole[n > 1] + Total@ Boole@ Map[AnyTrue[Partition[#, 2, 1], CoprimeQ @@ # &] &, Partition[Append[Divisors[n], n], 3, 1]], {n, 105}] (* _Michael De Vlieger_, Aug 19 2017 *)
%Y Cf. A136165, A136166, A136167.
%K nonn
%O 1,2
%A _Leroy Quet_, Dec 17 2007
%E More terms from _Diana L. Mecum_, Jul 11 2007, Jul 13 2008
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