Numbers k that, when expressed in base 4 and then interpreted in base 7, give a multiple of k.

Terms

a(0) =0a(1) =1a(2) =2a(3) =3a(4) =33a(5) =219a(6) =840a(7) =1055a(8) =4220a(9) =16880a(10) =95322a(11) =178500a(12) =714000a(13) =981540a(14) =1387680a(15) =7676775a(16) =7924262a(17) =12418476a(18) =12419535a(19) =16552116a(20) =19188717a(21) =44591130a(22) =66079524a(23) =77842213a(24) =178364520a(25) =294607851a(26) =363167196a(27) =610436322a(28) =823488858a(29) =950204780