A series of Siamese twin designs intersecting in a BIBD and a PBD

نویسنده

  • Dean Crnkovic
چکیده

Let p and 2p − 1 be prime powers and p ≡ 3 (mod 4). We describe a construction of a series of Siamese twin designs with Menon parameters (4p, 2p − p, p − p) intersecting in a derived design with parameters (2p − p, p − p, p − p − 1), and a pairwise balanced design PBD(2p − p, {p, p − p}, p − p − 1). When p and 2p − 1 are primes, the derived design and the pairwise balanced design are cyclic. Further, these two Menon designs with parameters (4p, 2p − p, p − p) lead to amicable regular Hadamard matrices of order 4p.

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

A few more BIBDs with k=8 or 9

It has been shown that for k = 8 or 9, there exists a BIBD(v, k, 1) for all positive integers v == 1 or k (mod k(k-1)), with some possible exceptions. We show that such designs exist for 49 of these exceptional values. A balanced incomplete block design (BIBD) with parameters (v, k, 1) is a pair (X, A) where X is a v-set and A is a family of k-subsets (where 2 < k < v) called blocks, such that ...

متن کامل

A class of Siamese twin Menon designs

A {0,±1}-matrix S is called a Siamese twin design sharing the entries of I, if S = I +K − L, where I,K,L are non-zero {0, 1}-matrices and both I + K and I + L are incidence matrices of symmetric designs with the same parameters. Let p and 2p−1 be prime powers and p ≡ 3 (mod 4). We describe a construction of a Siamese twin Menon design with parameters (4p, 2p − p, p − p), yielding a Siamese twin...

متن کامل

Group Divisible Designs with Two Associate Classes and λ2=1

A pairwise balanced design is an ordered pair S,B , denoted PBD S,B , where S is a finite set of symbols, and B is a collection of subsets of S called blocks, such that each pair of distinct elements of S occurs together in exactly one block of B. Here |S| v is called the order of the PBD. Note that there is no condition on the size of the blocks in B. If all blocks are of the same size k, then...

متن کامل

Pairwise Balanced Designs whose Block Size Set Contains Seven and Thirteen

In this paper, we investigate the PBD-closure of sets K with {7, 13} ⊆ K ⊆ {7, 13, 19, 25, 31, 37, 43}. In particular, we show that v ≡ 1 mod 6, v ≥ 98689 implies v ∈ B({7, 13}). As a preliminary result, many new 13-GDDs of type 13q and resolvable BIBD with block size 6 or 12 are also constructed. Furthermore, we show some elements to be not essential in a Wilson bases for the PBD-closed set {v...

متن کامل

The Study of different rations of spawning efficiency of siamese fighting fish (Bettasplendens)

The effects of five different foods including: blood worm, artemia cyst, Artemia mass powder, gammarus mass powder and ordinary commercial food were studied on Siamese fighting fish (Bettasplendens) propagation efficiency during thirty days in a Randomize Totally Design with 4 repeats .Experimental plots had been consisted of twenty 30*30*40 (cm) aquarium which a pair of male and female brood s...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:
  • Australasian J. Combinatorics

دوره 41  شماره 

صفحات  -

تاریخ انتشار 2008