A217180 a(n) is the number of digits in the decimal representation of the smallest power of n that contains five consecutive identical digits.
67, 131, 67, 88, 176, 146, 95, 131, 6, 163, 44, 253, 225, 255, 67, 290, 98, 148, 7, 138, 179, 255, 174, 131, 163, 158, 31, 239, 8, 60, 67, 242, 160, 170, 176, 32, 316, 327, 9, 192, 231, 190, 148, 240, 260, 228, 63, 146, 9, 64, 107, 206, 148, 159, 188, 250, 71
Offset: 2
Links
- V. Raman, Table of n, a(n) for n = 2..10000
Programs
-
Mathematica
Table[k = 1; While[d = IntegerDigits[n^k]; ! MemberQ[Partition[Differences[d], 4, 1], {0, 0, 0, 0}], k++]; Length[d], {n, 2, 100}] (* T. D. Noe, Oct 03 2012 *) Table[IntegerLength[NestWhile[n #&,n,SequenceCount[IntegerDigits[#],{x_,x_,x_,x_,x_}]<1&]],{n,2,60}] (* Harvey P. Dale, Jun 14 2025 *)
Comments