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A029785 Numbers k whose cube k^3 has no digit in common with k. 9
2, 3, 7, 8, 22, 27, 43, 47, 48, 52, 53, 63, 68, 77, 92, 157, 172, 177, 187, 188, 192, 222, 223, 252, 263, 303, 378, 408, 423, 442, 458, 468, 477, 478, 487, 527, 552, 558, 577, 587, 588, 608, 648, 692, 707, 772, 808, 818, 823, 843, 888, 918, 922 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Original name: Digits of n are not present in n^3.

Might be called "Exclusionary Cubes", although this might be reserved for terms having no duplicate digits, cf. link to rec.puzzles discussion group. Then the largest term would be 639172. - M. F. Hasler, Oct 17 2018

LINKS

Giovanni Resta, Table of n, a(n) for n = 1..1699 (terms < 10^19, first 528 terms from Charles R Greathouse IV)

Cliff Pickover et al, Exclusionary Squares and Cubes, rec.puzzles topic on google groups, January 2002

EXAMPLE

k = 80800000008880080808880080088 is in the sequence because the 87-digit number k^3 has only digits 1, ..., 7 and 9. - M. F. Hasler, Oct 16 2018

MATHEMATICA

Select[Range[5000], Intersection[IntegerDigits[#], IntegerDigits[#^3]]=={}&] (* Vincenzo Librandi, Oct 04 2013 *)

PROG

(PARI) is(n)=my(d=Set(digits(n))); setminus(d, Set(digits(n^3)))==d \\ Charles R Greathouse IV, Oct 02 2013

(PARI) is_A029785(n)=setintersect(Set(digits(n)), Set(digits(n^3)))==[] \\ M. F. Hasler, Oct 16 2018

CROSSREFS

Cf. A029786, A029783, A029784, A111116, A113316.

Sequence in context: A114281 A137823 A024540 * A045545 A029790 A206725

Adjacent sequences:  A029782 A029783 A029784 * A029786 A029787 A029788

KEYWORD

nonn,base

AUTHOR

Patrick De Geest

EXTENSIONS

Name reworded by Jon E. Schoenfield and M. F. Hasler, Oct 16 2018

STATUS

approved

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Last modified December 16 07:12 EST 2018. Contains 318158 sequences. (Running on oeis4.)