login
A081030
a(n) = largest k such that (sum of digits of k^n) >= k.
0
9, 17, 27, 36, 46, 64, 68, 74, 88, 117, 123, 138, 146, 154, 199, 204, 216, 232, 232, 242, 259, 256, 284, 323, 337, 344, 341, 357, 358, 396, 443, 393, 423, 465, 477, 484, 519, 521, 533, 518, 569, 597, 591, 626, 638, 682, 666, 667, 695, 712, 698, 739, 746, 784
OFFSET
1,1
EXAMPLE
a(2) = 17. We have 17^2 = 289 and 2+8+9 >= 17. No number > 17 has this property.
MATHEMATICA
(* 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 *)
CROSSREFS
KEYWORD
base,nonn
AUTHOR
David W. Wilson, Mar 02 2003
EXTENSIONS
Definition corrected by Harvey P. Dale, Oct 21 2011
STATUS
approved