OFFSET
1,1
LINKS
Rémy Sigrist, Table of n, a(n) for n = 1..25000
MATHEMATICA
normalQ[m_]:=Union[m]==Range[Max[m]];
Select[Range[2, 100], And[normalQ[FactorInteger[#][[All, 2]]], OrderedQ[Reverse[FactorInteger[#][[All, 2]]]]]&]
PROG
(PARI) is(n) = my (f=factor(n), w=#f~); if (w==0 || f[w, 2]!=1, return (0), for (k=1, w-1, if (f[k, 2]!=f[k+1, 2] && f[k, 2]!=1+f[k+1, 2], return (0)))
; return (1)) \\ Rémy Sigrist, Sep 05 2018
CROSSREFS
KEYWORD
nonn
AUTHOR
Gus Wiseman, Jul 21 2018
STATUS
approved