Number of strings of length n, formed from the 26-letter English alphabet, which contain the substring xy.
A215595
Number of strings of length n, formed from the 26-letter English alphabet, which contain the substring xy.
Terms
- a(0) =0a(1) =0a(2) =1a(3) =52a(4) =2027a(5) =70226a(6) =2280825a(7) =71112600a(8) =2155562551a(9) =64005323902
External references
- oeis: A215595