LETTERS-A,B,C,& D do not appear anywere in the
spellings of 1 to 99
LETTER D comes for the first time in hundred.
LETTERS A, B & C do not appear anywhere in the
spellings of 1 to 999..
LETTER A comes for the first time in thousand.
LETTERS B & C do not appear anywhere in the spellings
of 1 to 999,999,999..
LETTER B COMES FOR THE FIRST TIME IN bILLION. AND
LETTER C does not appear anywhere in the spellings of
entire english counting.