TY - JOUR
T1 - The computational complexity of decomposing block designs
AU - Colbourn, Charles J.
AU - Colbourn, Marlene J.
N1 - Funding Information:
*Research partially supported by NSERC Canada Grant A5483.
Funding Information:
**Research partially supported by NSERC Canada Grant A5047.
PY - 1985/1/1
Y1 - 1985/1/1
N2 - Deciding whether a (balanced incomplete) block design with λ = 3 can be decomposed, or partitioned, into block designs with smaller λ is shown to be NP-complete. The transformation employs known NP-completeness results on edge-partitioning graphs into triangles. The reduction also furnishes a construction of indecomposable triple systems with arbitrary odd λ, settling a question of Kramer.
AB - Deciding whether a (balanced incomplete) block design with λ = 3 can be decomposed, or partitioned, into block designs with smaller λ is shown to be NP-complete. The transformation employs known NP-completeness results on edge-partitioning graphs into triangles. The reduction also furnishes a construction of indecomposable triple systems with arbitrary odd λ, settling a question of Kramer.
UR - http://www.scopus.com/inward/record.url?scp=77956915144&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=77956915144&partnerID=8YFLogxK
U2 - 10.1016/S0304-0208(08)73027-5
DO - 10.1016/S0304-0208(08)73027-5
M3 - Article
AN - SCOPUS:77956915144
VL - 115
SP - 345
EP - 350
JO - North-Holland Mathematics Studies
JF - North-Holland Mathematics Studies
SN - 0304-0208
IS - C
ER -