A217164 a(n) is the least value of k such that the decimal expansion of n^k contains nine consecutive identical digits.

42485, 22791, 21243, 2796, 27717, 33836, 14162, 22076, 9, 9443, 11429, 16661, 16548, 11259, 10622, 14991, 5786, 28096, 9, 2890, 16736, 14116, 4549, 1398, 27735, 7597, 3614, 10332, 9, 4057, 8497, 9060, 23985, 2943, 13859, 11422, 13270, 5773, 9, 14777, 11541

Offset: 2

Author

V. Raman, Sep 27 2012

Keywords

• nonn
• base

Links

• V. Raman, Table of n, a(n) for n = 2..100

Crossrefs

Cf. A045875, A215727, A215728, A215729, A215730, A215731.

Programs

Mathematica

Table[k = 1; While[! MemberQ[Partition[Differences[IntegerDigits[n^k]], 8, 1], {0, 0, 0, 0, 0, 0, 0, 0}], k++]; k, {n, 2, 50}] (* T. D. Noe, Oct 01 2012 *)