From n >= 4 onward a(n) = 2. Outline of the proof by AK: As the sequence A094282 is forced to grow approximately like 2^n, it implies that the other terms in A094280 never "catch" the terms in A094282 and as the sum of the other elements on the n-th row of A094280 grows just polynomially (Cf. A006003), their contribution to the row sum is soon minimal and A094282 (with A094282(n+1)/A094282(n) tending to the limit 2, as n -> inf) defines solely the behavior of this sequence.