List of nuclides for which no decay modus was published/discovered,
but which surely are instable.

sym  A    Z   N    expected decay       expected life time

Mg  38   12  26    p or beta+              << 1 sec
Al  38   13  25    n or beta-              << 1 sec
Ti  38   22  16    p or beta+              << 1 sec
Si  42   14  28    n or beta-              << 1 sec

Kr  98   36  62    n or beta-              << 1 sec
In  98   49  49    p or beta+               < 1 sec
Sr 104   38  66    n or beta+              << 1 sec

Te 142   52  90    n or beta-              << 1 sec

Db 259  105 154    @ or fission or beta+    ~ 1 sec
Lr 263  103 160    @ or fission               ?
Bh 263  107 156    @ or fission or beta+   <~ 1 sec
Rf 264  104 160    @ or fission               ?
Db 264  105 159    @ or fission               ?
Sg 264  106 158    @ or fission               ?
Db 265  105 160    @ or fission               ?
Bh 265  107 158    @ or fission               ?
Mt 267  109 158    @ or fission               ?