Repeatedly subtract largest prime from n until either a prime or 1 remains.

Terms

a(0) =1a(1) =2a(2) =3a(3) =31a(4) =5a(5) =51a(6) =7a(7) =71a(8) =72a(9) =73a(10) =11a(11) =111a(12) =13a(13) =131a(14) =132a(15) =133a(16) =17a(17) =171a(18) =19a(19) =191a(20) =192a(21) =193a(22) =23a(23) =231a(24) =232a(25) =233a(26) =2331a(27) =235a(28) =29a(29) =291