Number of n-bead asymmetric bracelets with exactly 4 different colored beads.

A326789

Number of n-bead asymmetric bracelets with exactly 4 different colored beads.

Terms

    a(0) =0a(1) =0a(2) =0a(3) =3a(4) =24a(5) =124a(6) =588a(7) =2484a(8) =10240a(9) =40464a(10) =158220a(11) =608951a(12) =2333520a(13) =8894616a(14) =33864340a(15) =128791140a(16) =490027200a(17) =1865614976a(18) =7110959340a(19) =27138170397a(20) =103717719412a(21) =396965536224

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