4123173624
domain: N
Appears in sequences
- a(n) = 4^n - C(4,3)*3^n + C(4,2)*2^n - C(4,1).at n=15A000919
- Palindromes using exactly four different symbols.at n=30A056455
- Palindromes using exactly four different symbols.at n=31A056455
- Number of primitive (aperiodic) palindromes using exactly four different symbols.at n=30A056465
- Number of periodic palindromes using exactly four different symbols.at n=30A056490
- Number of primitive (period n) periodic palindromes using exactly four different symbols.at n=30A056500