60780720
domain: N
Appears in sequences
- a(n) = 4^n - C(4,3)*3^n + C(4,2)*2^n - C(4,1).at n=12A000919
- Number of primitive (aperiodic) words of length n which contain exactly four different symbols.at n=12A056269
- Palindromes using exactly four different symbols.at n=24A056455
- Palindromes using exactly four different symbols.at n=25A056455
- Number of primitive (aperiodic) palindromes using exactly four different symbols.at n=24A056465
- Number of periodic palindromes using exactly four different symbols.at n=24A056490
- Number of primitive (period n) periodic palindromes using exactly four different symbols.at n=24A056500
- Triangle T(n,k) read by rows = number of partitions of n-set into k blocks with distinct sizes, k = 1..A003056(n).at n=48A131632
- Number of set partitions of [n] into four blocks with distinct sizes.at n=6A272516