Number of partitions of {1,...,n} into block sizes a power of 2.

Terms

a(0) =1a(1) =1a(2) =2a(3) =4a(4) =11a(5) =31a(6) =106a(7) =372a(8) =1500a(9) =6220a(10) =28696a(11) =136016a(12) =702802a(13) =3727946a(14) =21253324a(15) =124231096a(16) =772458367a(17) =4918962479a(18) =33061095118a(19) =227303570524