a(1) = 1, a(2n) = smallest composite number > (2n-1)-th partial sum of the sequence itself and a(2n+1) = smallest prime > 2n-th partial sum of the sequence.

A076975

a(1) = 1, a(2n) = smallest composite number > (2n-1)-th partial sum of the sequence itself and a(2n+1) = smallest prime > 2n-th partial sum of the sequence.

Terms

    a(0) =1a(1) =4a(2) =7a(3) =14a(4) =29a(5) =56a(6) =113a(7) =225a(8) =457a(9) =908a(10) =1823a(11) =3638a(12) =7283a(13) =14559a(14) =29123a(15) =58241a(16) =116483a(17) =232965a(18) =465931a(19) =931861a(20) =1863731a(21) =3727453a(22) =7454933a(23) =14909839a(24) =29819701a(25) =59639379a(26) =119278801a(27) =238557559a(28) =477115271a(29) =954230389

External references