Total number of occurrences of the pattern 1=2=3 in all preferential arrangements (or ordered partitions) of n elements.

A240798

Total number of occurrences of the pattern 1=2=3 in all preferential arrangements (or ordered partitions) of n elements.

Terms

    a(0) =0a(1) =0a(2) =1a(3) =12a(4) =130a(5) =1500a(6) =18935a(7) =262248a(8) =3972612a(9) =65500200a(10) =1169398065a(11) =22494463860a(12) =464072915878

External references