Number of nonisomorphic binary n X n matrices with two 1's per column under row and column permutations.
A247417
Number of nonisomorphic binary n X n matrices with two 1's per column under row and column permutations.
Terms
- a(0) =1a(1) =3a(2) =11a(3) =35a(4) =132a(5) =471a(6) =1806a(7) =7042a(8) =28494a(9) =118662a(10) =510517a(11) =2262738a(12) =10337474a(13) =48625631a(14) =235357470a(15) =1171163995a(16) =5986424739a(17) =31403695142a(18) =168913667164a(19) =930739116386
External references
- oeis: A247417