Third column of A027446.

Terms

a(0) =2a(1) =7a(2) =47a(3) =57a(4) =459a(5) =1023a(6) =3349a(7) =3601a(8) =42131a(9) =44441a(10) =605453a(11) =631193a(12) =655217a(13) =1355479a(14) =23763863a(15) =24444543a(16) =476698557a(17) =488338185a(18) =499423545a(19) =510005025a(20) =11962908135a(21) =12186001005a(22) =62000850801a(23) =63030510201a(24) =192066102203a(25) =194934439103