OFFSET
1,1
LINKS
Harvey P. Dale, Table of n, a(n) for n = 1..1000
MATHEMATICA
Table[Max[Flatten[FactorInteger[{n, 2 n+1}], 1][[All, 1]]], {n, 70}] (* Harvey P. Dale, Mar 25 2020 *)
PROG
(PARI) gpf(n)=local(ps); if(n<2, n, ps=factor(n)[, 1]~; ps[#ps])
vector(80, n, gpf(n*(2*n+1)))
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Franklin T. Adams-Watters, Nov 06 2011
STATUS
approved