OFFSET
1,2
EXAMPLE
MATHEMATICA
a[n_]:=a[n]=Min@Select[Divisors[max=t=k=0; While[t<n, k++; While[(d=DivisorSigma[0, k])<=max, k++]; max=d; t++]; k], FreeQ[Array[a, n-1], #]&]; Array[a, 30] (* Giorgos Kalogeropoulos, Jan 13 2022 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
J. Lowell, Jan 13 2022
EXTENSIONS
More terms from Amiram Eldar, Jan 13 2022
STATUS
approved