$284 457$ Steiner triple systems of order $19$ contain a subsystem of order $9$
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- by D. R. Stinson and E. Seah PDF
- Math. Comp. 46 (1986), 717-729 Request permission
Abstract:
In this paper, we enumerate the (nonisomorphic) Steiner triple systems of order 19 which contain a subsystem of order 9. The number of these designs is precisely 284457. We also determine which of these designs also contain at least one subsystem of order 7, and how many. Exactly 13529 of them contain at least one subsystem of order 7.References
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Additional Information
- © Copyright 1986 American Mathematical Society
- Journal: Math. Comp. 46 (1986), 717-729
- MSC: Primary 05B07; Secondary 20B25
- DOI: https://doi.org/10.1090/S0025-5718-1986-0829642-7
- MathSciNet review: 829642