OFFSET
1,1
LINKS
Seiichi Manyama, Table of n, a(n) for n = 1..10000
EXAMPLE
21 (= 23 - 2) is squarefree. So 23 is not a term.
27 = 3^3 and 28 = 2^2*7. So 29 is a term.
MATHEMATICA
Select[Prime[Range[500]], !SquareFreeQ[# - 2] && !SquareFreeQ[# - 1] &] (* Vincenzo Librandi, Sep 06 2018 *)
PROG
(PARI) forprime(p=2, 1e4, if(!issquarefree(p-1)&&!issquarefree(p-2), print1(p, ", "))); \\ Altug Alkan, Sep 06 2018
(Magma) [p: p in PrimesInInterval(3, 2500)| not IsSquarefree(p-2) and not IsSquarefree(p-1)]; // Vincenzo Librandi, Sep 06 2018
CROSSREFS
KEYWORD
nonn
AUTHOR
Seiichi Manyama, Sep 06 2018
STATUS
approved