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Letters ‘a’, ‘b’, ‘c’ and ‘d’ do not appear if you spell any of the numbers between 1 and 99.
Funnily enough, letter ‘d’ comes for the first time in the word Hundred.
In addition, letters ‘a’, ‘b’ and ‘c’ do not appear anywhere in the spellings of 1 to 999.
Strange, but true, letter ‘a’ comes for the first time in the word Thousand.
Neither letter ‘b’ nor ‘c’ appear anywhere in the spellings of 1 to 999,999,999.
[You will see the letter ‘b’ for the first time in the word Billion.
Letter ‘c’ does not appear anywhere in the spellings of entire English counting words.
