maximum possible number of rows in one block

What is the practical maximum number of rows that can stored on a single block?
Not theoretical.
Also, one column, all all rows null, is not very "practical".
My answer: 2967 rows.
No change for:
initrans
maxtrans
compress
bigfile

SQL> create smallfile tablespace sfts32 blocksize 32k datafile size 16m autoextend on next 16m;

Tablespace created.

SQL> create table tsfts32 ( c char(1) ) tablespace sfts32 pctfree 0;

Table created.

SQL> insert into tsfts32 select null from dual connect by level <= 1000000;

1000000 rows created.

SQL> select max(dbms_rowid.rowid_row_number(rowid)) from tsfts32;

MAX(DBMS_ROWID.ROWID_ROW_NUMBER(ROWID))
---------------------------------------
                                   2966


SQL> select dbms_rowid.rowid_to_absolute_fno(rowid,user,'TSFTS32') from tsfts32 where rownum = 1;

DBMS_ROWID.ROWID_TO_ABSOLUTE_FNO(ROWID,USER,'TSFTS32')
------------------------------------------------------
                                                  1032

SQL> select dbms_rowid.rowid_block_number(rowid) from tsfts32 where rownum = 1;

DBMS_ROWID.ROWID_BLOCK_NUMBER(ROWID)
------------------------------------
                                 419


SQL> alter system dump datafile 1032 block 419;

System altered.

SQL> @ tracefilename.sql

TRACEFILENAME
----------------------------------------------------------------------------------------------------
/u01/app/oracle/diag/rdbms/db12201/db12201/trace/db12201_ora_19214.trc

data_block_dump,data header at 0x7fe87b727064
===============
tsiz: 0x7f98
hsiz: 0x1740
pbl: 0x7fe87b727064
     76543210
flag=--------
ntab=1
nrow=2967
frre=-1
fsbo=0x1740
fseo=0x5cd3
avsp=0x9
tosp=0x9
0xe:pti[0]      nrow=2967       offs=0
etc.
tab 0, row 2966, @0x5d9f
tl: 3 fb: --H-FL-- lb: 0x1  cc: 0
end_of_block_dump