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.
%I A001200 M0726 N0271 #53 Apr 19 2025 19:37:06 %S A001200 1,1,1,2,3,5,10,24,69,384,5250,232929,28872973 %N A001200 Number of linear geometries on n (unlabeled) points. %C A001200 For the labeled case see A056642. %C A001200 Also a(n) = 1 + number of non-isomorphic simple rank-3 matroids on n elements (see A058731); a(n) = number of non-isomorphic 2-partitions of a set of size n. For 1-partitions see A000041. %D A001200 L. Comtet, Advanced Combinatorics, Reidel, 1974, p. 303, #42. %D A001200 CRC Handbook of Combinatorial Designs, 1996, pp. 216, 697. %D A001200 J. Doyen, Sur le nombre d'espaces linéaires non isomorphes de n points. Bull. Soc. Math. Belg. 19 1967 421-437. %D A001200 P. Robillard, On the weighted finite linear spaces. Bull. Soc. Math. Belg. 22 (1970), 227-241. %D A001200 N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence). %D A001200 N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence). %H A001200 Mohamed Barakat, Reimer Behrends, Christopher Jefferson, Lukas Kühne, Martin Leuner, <a href="https://arxiv.org/abs/1907.01073">On the generation of rank 3 simple matroids with an application to Terao's freeness conjecture</a>, arXiv:1907.01073 [math.CO], 2019. %H A001200 A. Betten and D. Betten, <a href="https://doi.org/10.1002/(SICI)1520-6610(1999)7:2%3C119::AID-JCD5%3E3.0.CO;2-W">Linear spaces with at most 12 points</a>, J. Combinatorial Designs, Volume 7, 1999, pp. 119 - 145. %H A001200 J. E. Blackburn, H. H. Crapo, and D. A. Higgs, <a href="https://doi.org/10.1090/S0025-5718-1973-0419270-0">A catalogue of combinatorial geometries</a>, Math. Comp 27 1973 155-166. %H A001200 J. Doyen, <a href="/A001200/a001200.pdf">Sur le nombre d'espaces linéaires non isomorphes de n points</a> [Annotated and scanned copy] %H A001200 D. G. Glynn, <a href="https://doi.org/10.1016/0097-3165(88)90027-1">Rings of geometries II</a>, J. Combin. Theory, A 49 (1988), 26-66. %H A001200 D. G. Glynn, <a href="https://www.researchgate.net/publication/230899821">A geometrical isomorphism algorithm</a>, Bull. ICA 7 (1993), 36-38. %H A001200 Robert Haas, <a href="https://arxiv.org/abs/1905.12627">Cographs</a>, arXiv:1905.12627 [math.GM], 2019. %H A001200 G. Heathcote, <a href="https://doi.org/10.1002/jcd.3180010505">Linear spaces on 16 points</a>, J. Combin. Designs, Vol. 1, No. 5 (1993), 359-378. %H A001200 Nathan Kaplan, Susie Kimport, Rachel Lawrence, Luke Peilen and Max Weinreich, <a href="https://doi.org/10.1007/s00022-017-0391-1">Counting arcs in projective planes via Glynn's algorithm</a>, J. Geom. 108, No. 3, 1013-1029 (2017). %H A001200 Ch. Pietsch, <a href="https://doi.org/10.1002/jcd.3180030305">On the classification of linear spaces of order 11</a>, J. Comb. Designs, Vol. 3, No. 3 (1995), 185-193. %Y A001200 Cf. A000041, A056642, A058731, A001548. %K A001200 nonn,hard,more,nice %O A001200 0,4 %A A001200 _N. J. A. Sloane_, D.Glynn(AT)math.canterbury.ac.nz