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A084661 Numbers k such that k + sum_of_digits(k) is a cube. 1
4, 18, 121, 198, 207, 329, 720, 977, 1318, 2183, 2731, 3357, 4082, 4891, 4900, 5814, 6836, 7969, 9243, 10634, 12154, 13797, 13806, 15611, 17554, 19656, 21929, 24367, 26973, 29759, 32746, 39281, 42853, 46629, 54850, 59292, 59301, 63968, 68890, 74070, 79475 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

A066564 lists numbers k such that k + sum_of_digits(k) is a square.

LINKS

Harvey P. Dale, Table of n, a(n) for n = 1..250

EXAMPLE

a(3)=121 because 121 + (1 + 2 + 1) = 125 = 5^3.

MATHEMATICA

Select[Range[80000], IntegerQ[Surd[#+Total[IntegerDigits[#]], 3]]&] (* Harvey P. Dale, Sep 13 2018 *)

PROG

(PARI) isok(n) = ispower(n + sumdigits(n), 3); \\ Michel Marcus, Oct 09 2013

CROSSREFS

Cf. A007953, A066564.

Sequence in context: A053529 A005442 A306881 * A112294 A346680 A292500

Adjacent sequences:  A084658 A084659 A084660 * A084662 A084663 A084664

KEYWORD

easy,nonn,base

AUTHOR

Zak Seidov, Jun 29 2003

EXTENSIONS

More terms from Michel Marcus, Oct 04 2013

STATUS

approved

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Last modified August 4 10:01 EDT 2021. Contains 346446 sequences. (Running on oeis4.)