a(n) = (A376907(n) - 10^(n-1))/3.

Terms

a(0) =2a(1) =3a(2) =9a(3) =219a(4) =89a(5) =707a(6) =7139a(7) =17397a(8) =127107a(9) =185573a(10) =170099a(11) =8513673a(12) =3730629a(13) =9645947a(14) =20878187a(15) =435128997a(16) =413502597a(17) =7180622897a(18) =28071202809a(19) =4197184407a(20) =53159437779a(21) =72827487477a(22) =408466487673