1,1
Wikipedia, Letter frequencies
D is the 10th most common letter in the English language and it is the fourth letter in the alphabet. So the fourth number in this sequence is 10.
Sequence in context: A013332 A063871 A084316 * A115280 A081849 A169642
Adjacent sequences: A126807 A126808 A126809 * A126811 A126812 A126813
word,easy,fini,full,nonn
Daniel Drucker (dmd(AT)3e.org), Feb 23 2007