

A166987


Members of A143610 for which both neighbors are squarefree.


0



72, 108, 200, 392, 500, 968, 1352, 1372, 4232, 7688, 8788, 13448, 14792, 17672, 19652, 27436, 27848, 35912, 48668, 49928, 55112, 75272, 81608, 84872, 97556, 102152, 119164, 137288, 150152, 154568, 177608, 182408, 197192, 202612, 223112
(list;
graph;
refs;
listen;
history;
text;
internal format)



OFFSET

1,1


COMMENTS

Numbers of the form n=p^2*q^3 where p and q are two different primes and where n+1 and n1 are both in A005117.


LINKS

Table of n, a(n) for n=1..35.


MATHEMATICA

f[n_]:=Last/@FactorInteger[n]=={2, 3}Last/@FactorInteger[n]=={3, 2}; << NumberTheory`NumberTheoryFunctions` lst={}; Do[If[f[n], If[SquareFreeQ[n1]&&SquareFreeQ[n+1], AppendTo[lst, n]]], {n, 3*9!}]; lst


CROSSREFS

Cf. A067874.
Sequence in context: A052486 A114128 A143610 * A251124 A169644 A078667
Adjacent sequences: A166984 A166985 A166986 * A166988 A166989 A166990


KEYWORD

nonn


AUTHOR

Vladimir Joseph Stephan Orlovsky, Oct 26 2009


EXTENSIONS

Definition narrowed by R. J. Mathar, Oct 28 2009


STATUS

approved



