OFFSET
0,2
LINKS
MATHEMATICA
Array[Floor@ Total@ Flatten@ MapIndexed[#1 2^(#2 - 1) &, Flatten[Table[2^(PrimePi@ #1 - 1), {#2}] & @@@ FactorInteger@ DivisorSigma[1, #]]] &@ Block[{p = Partition[Split[Join[IntegerDigits[#, 2], {2}]], 2], q}, Times @@ Flatten[Table[q = Take[p, -i]; Prime[Count[Flatten[q], 0] + 1]^q[[1, 1]], {i, Length[p]}]]] &, 70, 0] (* Michael De Vlieger, Feb 12 2020, after Robert G. Wilson v at A005940 *)
PROG
CROSSREFS
KEYWORD
nonn
AUTHOR
Antti Karttunen, Feb 12 2020
STATUS
approved