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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A374939 a(n) is the number of distinct Legendrian knots, up to smooth knot type and classical invariants, with nonnegative rotation numbers that can be realized on a Legendrian n-mosaic.

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%I A374939 #17 Aug 09 2024 08:01:26
%S A374939 0,1,4,9,40,328
%N A374939 a(n) is the number of distinct Legendrian knots, up to smooth knot type and classical invariants, with nonnegative rotation numbers that can be realized on a Legendrian n-mosaic.
%C A374939 A Legendrian n-mosaic is an n X n array of the 10 tiles given in Figure 5 of Pezzimenti and Pandey. These tiles represent part of a Legendrian curve in the front projection.
%C A374939 The classical invariants of Legendrian knots are the Thurston-Bennequin invariant and the rotation number.
%H A374939 Margaret Kipe, <a href="/A374939/a374939.py.txt">Python</a>
%H A374939 Margaret Kipe, <a href="/A374939/a374939.rs.txt">Rust</a>
%H A374939 S. Pezzimenti and A. Pandey, <a href="https://doi.org/10.1142/S021821652250002X">Geography of Legendrian knot mosaics</a>, Journal of Knot Theory and its Ramifications, 31 (2022), article no. 2250002, 1-22.
%e A374939 For n = 3 there are exactly a(3) = 4 distinct Legendrian knots with nonnegative rotation numbers that can be realized on a Legendrian 3-mosaic, namely the four Legendrian unknots whose Thurston-Bennequin invariants are -1, -2, -3, and -3 and whose rotation numbers are 0, 1, 0, and 2, respectively.
%o A374939 (Python, Rust) //See Margaret Kipe links
%Y A374939 Cf. A374942, A374943, A374944, A374945, A374946, A374947.
%K A374939 nonn,hard,more
%O A374939 1,3
%A A374939 _Margaret Kipe_, _Samantha Pezzimenti_, _Leif Schaumann_, _Luc Ta_, _Wing Hong Tony Wong_, Jul 24 2024