a(n) is number of digits of the smallest term of the sequence A248857 which is of the form 4^n*(5^(2n-1)*10^m-1).
A248858
a(n) is number of digits of the smallest term of the sequence A248857 which is of the form 4^n*(5^(2n-1)*10^m-1).
Terms
- a(0) =4a(1) =5a(2) =7a(3) =10a(4) =14a(5) =14a(6) =16a(7) =17a(8) =42a(9) =24a(10) =47a(11) =25a(12) =29a(13) =39a(14) =31a(15) =40a(16) =41a(17) =45a(18) =40a(19) =69a(20) =46a(21) =65a(22) =807a(23) =128a(24) =67a(25) =89a(26) =55a(27) =217a(28) =87a(29) =76
External references
- oeis: A248858