Number of step shifted (decimated) sequence structures using a maximum of four different symbols.

A056393

Number of step shifted (decimated) sequence structures using a maximum of four different symbols.

Terms

    a(0) =1a(1) =2a(2) =4a(3) =11a(4) =17a(5) =107a(6) =131a(7) =811a(8) =1893a(9) =11107a(10) =17599a(11) =179371a(12) =233449a(13) =1866057a(14) =5603787a(15) =22469291a(16) =44744047a(17) =477262537a(18) =636308685a(19) =5732457131a(20) =15272176697a(21) =73301054891a(22) =133274359129

External references