A361282 Number of rank n+1 simple connected series-parallel matroids on [2n].
0, 1, 75, 9345, 1865745, 554479695, 231052877055, 128938132548225, 92986310399407425, 84250567868935042575, 93744545254140599193375, 125717783386887888296925825, 200041202339679732328342670625, 372688996228146502285257581079375, 803768398459351988653830600415029375
Offset: 1
Keywords
Examples
For n=2 the a(2) = 1 rank 3 simple connected series-parallel matroid on [4] is the uniform matroid of rank 3.
Links
- Luis Ferroni and Matt Larson, Kazhdan-Lusztig polynomials of braid matroids, arXiv:2303.02253 [math.CO], 2023.
Programs
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PARI
a(n) = T(2*n)[2*n][n+1] \\ T(n) defined in A361355. - Andrew Howroyd, Mar 09 2023
Extensions
Terms a(10)-a(15) from Andrew Howroyd, Mar 09 2023