cibd 10.0: Program for Constructing cyclic IBDs of size (v,k,r)
(c) 2018 Design Computing (http://designcomputing.net/)

Note: Best cyclic IBD for v=12, k=4, r=6, b=18

Try	iter	E	E/U	Concurrences
1	1	0.812	0.998	1(4) 2(7) 

Initial block(s) and the no. of blocks generated by each initial block for try 1 using seed 1533475331345:

0	7	11	2	 (12)
0	4	6*	10*	 (6)

Plan (blocks are columns):

6	8	2	10	4	8	0	0	3	7	10	2	11	1	7	10	10	0	
4	6	9	7	2	9	4	10	0	2	1	3	5	9	1	4	6	8	
11	1	7	8	9	11	7	5	1	0	6	5	3	3	11	2	0	2	
3	5	6	3	1	4	5	9	8	11	11	10	9	7	5	8	4	6	

Note: cibd used 0.114 seconds.
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