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A112994 Numbers whose cubes are exclusionary: numbers n such that n and n^3 have no digits in common. 3
2, 3, 7, 8, 27, 43, 47, 48, 52, 53, 63, 68, 92, 157, 172, 187, 192, 263, 378, 408, 423, 458, 468, 478, 487, 527, 587, 608, 648, 692, 823, 843, 918, 1457, 1587, 1592, 4657, 4732, 5692, 6058, 6378, 7658 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

A number n with no repeated digits has an exclusionary cube n^3 if the latter is made up of digits not appearing in n. (This is a subsequence of A029785.) For the corresponding exclusionary cubes see A112993. Conjectured to be complete.

REFERENCES

H. Ibstedt, Solution to Problem 2623, "Exclusionary Powers", pp. 346-9, Journal of Recreational Mathematics, vol. 32 No.4 2003-4 Baywood NY.

Clifford A. Pickover, A Passion for Mathematics, Wiley, 2005; see p. 60.

LINKS

Table of n, a(n) for n=1..42.

Clifford A. Pickover, Extreme Challenges in Mathematics and Morals

PROG

(PARI) isok(n) = my(digs = digits(n)); (#digs == #Set(digs)) && (#setintersect(Set(digs), Set(digits(n^3))) == 0); \\ Michel Marcus, Oct 26 2013

CROSSREFS

The corresponding cubes are in A112993.

Sequence in context: A029790 A206725 A129645 * A056036 A056432 A271506

Adjacent sequences:  A112991 A112992 A112993 * A112995 A112996 A112997

KEYWORD

nonn,base,fini

AUTHOR

Lekraj Beedassy, Oct 13 2005

EXTENSIONS

Missing term 468 added by N. J. A. Sloane, May 22 2008

STATUS

approved

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Last modified September 26 05:09 EDT 2017. Contains 292502 sequences.