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

A056398

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

Terms

    a(0) =0a(1) =0a(2) =0a(3) =1a(4) =3a(5) =37a(6) =63a(7) =479a(8) =1316a(9) =8597a(10) =14619a(11) =155999a(12) =211231a(13) =1732907a(14) =5302823a(15) =21559909a(16) =43398413a(17) =466495335a(18) =625545865a(19) =5659500031a(20) =15126813765a(21) =72778025365a(22) =132561145173

External references