Numbers k where A121561(k) = 4.

Terms

a(0) =1357323a(1) =1357324a(2) =1562041a(3) =1562042a(4) =1671903a(5) =1671904a(6) =1889953a(7) =1889954a(8) =2010855a(9) =2010856a(10) =3826141a(11) =3826142a(12) =3851581a(13) =3851582a(14) =3933721a(15) =3933722a(16) =4652475a(17) =4652476a(18) =4652501a(19) =4738773a(20) =4738774a(21) =5518809a(22) =5518810a(23) =5826123