OFFSET
1,2
COMMENTS
The corresponding numbers of divisors are 1, 2, 3, 4, 6, 8, 9, 10, 12, 16, 18, 20, ...
a(13) > 1.5*10^11, if it exists.
MATHEMATICA
bw[n_] := DigitCount[n, 2, 1]; q[n_] := Module[{d = Divisors[n]}, Union[bw /@ d] == Range[Length[d]]]; seq = {}; dm = 0; Do[If[(d = DivisorSigma[0, n]) > dm && q[n], dm = d; AppendTo[seq, n]], {n, 1, 10^5, 2}]; seq
CROSSREFS
KEYWORD
nonn,base,more
AUTHOR
Amiram Eldar, Jun 04 2022
STATUS
approved