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A081030 a(n) = largest k such that (sum of digits of k^n) >= k. 0

%I #9 Aug 03 2014 14:01:19

%S 9,17,27,36,46,64,68,74,88,117,123,138,146,154,199,204,216,232,232,

%T 242,259,256,284,323,337,344,341,357,358,396,443,393,423,465,477,484,

%U 519,521,533,518,569,597,591,626,638,682,666,667,695,712,698,739,746,784

%N a(n) = largest k such that (sum of digits of k^n) >= k.

%e a(2) = 17. We have 17^2 = 289 and 2+8+9 >= 17. No number > 17 has this property.

%t (* the constant 20 may need to be higher for larger n *) Table[Select[Range[20*n], Total[IntegerDigits[#^n]] >= # &][[-1]], {n, 100}] (* _T. D. Noe_, Oct 21 2011 *)

%Y Cf. A055568, A055569, A055570, A055571, A055572.

%K base,nonn

%O 1,1

%A _David W. Wilson_, Mar 02 2003

%E Definition corrected by Harvey P. Dale, Oct 21 2011

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Last modified March 28 04:13 EDT 2024. Contains 371235 sequences. (Running on oeis4.)