Number of n-digit semiprimes with semiprime digits (4, 6, 9).
A254715
Number of n-digit semiprimes with semiprime digits (4, 6, 9).
Terms
- a(0) =3a(1) =4a(2) =8a(3) =18a(4) =55a(5) =137a(6) =415a(7) =941a(8) =2854a(9) =7743a(10) =21959a(11) =61545a(12) =175817a(13) =496688
External references
- oeis: A254715