Sum over all partitions of n of the bitwise OR of the parts.

Terms

a(0) =0a(1) =1a(2) =3a(3) =7a(4) =13a(5) =23a(6) =40a(7) =67a(8) =103a(9) =156a(10) =231a(11) =340a(12) =486a(13) =689a(14) =964a(15) =1352a(16) =1845a(17) =2507a(18) =3363a(19) =4500a(20) =5937a(21) =7814a(22) =10174a(23) =13247a(24) =17064a(25) =21930a(26) =27957a(27) =35616a(28) =45009a(29) =56805