A list whith the following 6 components:
  
- number
 
numeric. The ACNUC number of the sequence.
  
- length
 
numeric. The length of the sequence.
  
- frame
 
numeric. The reading frame (0, 1, or 2) of the sequence for CDS.
  
- gencode
 
numeric. ACNUC's genetic code (0 means universal) of the sequence for CDS.
  
- ncbigc
 
numeric. NCBI's genetic code (0 means universal) of the sequence for CDS.
  
- otheraccessmatches
 
logical. If TRUE it means that several sequences are attached
    to the given accession nunmber, and that only the ACNUC number of the first attached
   sequence is returned in the number component of the list.
isn(what, ...) is a shortcut for isenum(what, ...)$number.
As from seqinR 1.1-3 getNumber.socket and
getAttributsocket are deprecated (a warning is issued).