Number of decimal digits of A008559.

Terms

a(0) =1a(1) =2a(2) =4a(3) =10a(4) =31a(5) =100a(6) =330a(7) =1093a(8) =3628a(9) =12049a(10) =40023a(11) =132951a(12) =441651a(13) =1467130a(14) =4873698a(15) =16190071a(16) =53782249a(17) =178660761a(18) =593498199a(19) =1971558339a(20) =6549375034a(21) =21756552927a(22) =72273704413