Sum of odd Fermat coefficients rounded to nearest integer.

Terms

a(0) =1a(1) =1a(2) =2a(3) =4a(4) =9a(5) =20a(6) =46a(7) =105a(8) =246a(9) =583a(10) =1393a(11) =3355a(12) =8133a(13) =19825a(14) =48554a(15) =119412a(16) =294761a(17) =729980a(18) =1813107a(19) =4515225a(20) =11271198a(21) =28196896a(22) =70679137a(23) =177487714a(24) =446446560a(25) =1124706145a(26) =2837445500a(27) =7167878628a(28) =18129622761a(29) =45907772900