Number of step shifted (decimated) sequences using exactly four different symbols.

A056378

Number of step shifted (decimated) sequences using exactly four different symbols.

Terms

    a(0) =0a(1) =0a(2) =0a(3) =12a(4) =60a(5) =792a(6) =1404a(7) =10716a(8) =31200a(9) =205032a(10) =349956a(11) =3727932a(12) =5065804a(13) =41574312a(14) =127199028a(15) =517290132a(16) =1041517620a(17) =11195637720a(18) =15012935676a(19) =135825699612a(20) =363040469732

External references