Number of compositions of n with first part 3 and no equal adjacent parts; this is column 3 of the array in A096568.

A096571

Number of compositions of n with first part 3 and no equal adjacent parts; this is column 3 of the array in A096568.

Terms

    a(0) =0a(1) =0a(2) =1a(3) =1a(4) =1a(5) =2a(6) =3a(7) =6a(8) =12a(9) =20a(10) =33a(11) =59a(12) =104a(13) =181a(14) =319a(15) =557a(16) =971a(17) =1705a(18) =2985a(19) =5218a(20) =9138a(21) =15993a(22) =27984a(23) =48992a(24) =85749a(25) =150061a(26) =262656a(27) =459721a(28) =804597a(29) =1408263

External references