((Cumulative sum A000045) + (A000079)) - A092176.

Terms

a(0) =1a(1) =2a(2) =3a(3) =6a(4) =11a(5) =23a(6) =45a(7) =89a(8) =172a(9) =331a(10) =641a(11) =1239a(12) =2405a(13) =4685a(14) =9156a(15) =17955a(16) =35323a(17) =69687a(18) =137804a(19) =273055a(20) =541963a(21) =1077194a(22) =2143479a(23) =4269285a(24) =8509953