Abstract
Quasi-symmetric designs with intersection numbers x > 0 and y = x + 2 under the condition λ > 1 are investigated. If D(v, b, r, k, λ; x, y) is a quasi-symmetric design with above conditions then it is shown that either λ = x + 1 or x + 2 or D is a design with the parameters given in the Table 6 or complement of one of these designs.
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Pawale, R.M. Quasi-symmetric designs with the difference of block intersection numbers two. Des. Codes Cryptogr. 58, 111–121 (2011). https://doi.org/10.1007/s10623-010-9384-x
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DOI: https://doi.org/10.1007/s10623-010-9384-x