OFFSET
1,1
LINKS
Amiram Eldar, Table of n, a(n) for n = 1..10000
MATHEMATICA
Select[Range[750], And @@ SquareFreeQ /@ {#, # + 1} && !SquareFreeQ[2# + 1] &] (* Amiram Eldar, Mar 22 2020 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Artur Jasinski, Jan 28 2010
STATUS
approved