Dedekind number

File:Monotone Boolean functions 0,1,2,3.svg|400px|thumb|right|[[File:Loupe light.svg|15px|link=http://upload.wikimedia.org/wikipedia/commons/thumb/5/57/Monotone_Boolean_functions_0%2C1%2C2%2C3.svg/1500px-Monotone_Boolean_functions_0%2C1%2C2%2C3.svg.png]] The free distributive lattices of monotonic Boolean functions on 0, 1, 2, and 3 arguments, with 2, 3, 6, and 20 elements respectively (move mouse over right diagram to see description) circle 659 623 30 [[File:Boolean function 0000 0000.svg|contradiction]] circle 658 552 35 [[File:Boolean functions like 1000 0000.svg|A and B and C]] circle 587 480 35 [[File:Boolean functions like 1000 1000.svg|A and B]] circle 659 481 35 [[File:Boolean functions like 1010 0000.svg|A and C]] circle 729 481 35 [[File:Boolean functions like 1100 0000.svg|B and C]] circle 588 410 35 [[File:Boolean functions like 1010 1000.svg|(A and B) or (A and C)]] circle 658 410 35 [[File:Boolean functions like 1100 1000.svg|(A and B) or (B and C)]] circle 729 410 35 [[File:Boolean functions like 1110 0000.svg|(A and C) or (B and C)]] circle 548 339 30 [[File:Boolean functions like 1010 1010.svg|A]] circle 604 339 30 [[File:Boolean functions like 1100 1100.svg|B]] circle 758 339 30 [[File:Boolean functions like 1111 0000.svg|C]] circle 661 339 35 [[File:Boolean functions like 1110 1000.svg|(A or B) and (A or C) and (B or C) (A and B) or (A and C) or (B and C)]] circle 588 268 35 [[File:Boolean functions like 1110 1010.svg|(A or B) and (A or C)]] circle 659 267 35 [[File:Boolean functions like 1110 1100.svg|(A or B) and (B or C)]] circle 729 268 35 [[File:Boolean functions like 1111 1000.svg|(A or C) and (B or C)]] circle 588 197 35 [[File:Boolean functions like 1110 1110.svg|A or B]] circle 658 197 35 [[File:Boolean functions like 1111 1010.svg|A or C]] circle 729 197 35 [[File:Boolean functions like 1111 1100.svg|B or C]] circle 658 126 35 [[File:Boolean functions like 1111 1110.svg|A or B or C]] circle 659 56 30 [[File:Boolean function 1111 1111.