OFFSET
1,1
MATHEMATICA
FromDigits[IntegerDigits[#, 4]]&/@(2^MersennePrimeExponent[Range[20]]-1) (* Harvey P. Dale, Mar 25 2023 *)
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Juri-Stepan Gerasimov, Jun 16 2009
EXTENSIONS
Keyword:base added by R. J. Mathar, Aug 03 2009
STATUS
approved