Number of irreducible positions of size n in Montreal solitaire.

Terms

a(0) =1a(1) =2a(2) =4a(3) =11a(4) =28a(5) =77a(6) =209a(7) =573a(8) =1576a(9) =4340a(10) =11964a(11) =33004a(12) =91080a(13) =251407a(14) =694065a(15) =1916306a(16) =5291223a(17) =14610468a(18) =40344380a(19) =111406090a(20) =307637516a(21) =849517917a(22) =2345890032a(23) =6478044971a(24) =17888793238a(25) =49399054113a(26) =136413247359a(27) =376699178348