The pattern represents word lengths: E (Eight-5), D (?), T (Twenty-6), C (?), P (Five-4), C (Four-4), S (Six-3), A (Eight-5 no), A (Ace-3 no). Actually: E (8-5 letters), D (?), T (3-5 letters), C (?), P (5-4 letters), C (4-4 letters), S (6-3 letters), A (?), A (?). Better: This is 'Eight, D, Three, C, Five, Four, Six, A' where each letter is the first letter and the blank positions need 'Five' (P) and 'Four' (C) to complete the pattern.