

A061111


a(1) = 1; a(n) = smallest number such that the concatenation a(1).0^*.a(2).0^*....0^*.a(n) is a perfect cube (where any number of 0's can be inserted between the terms).


0




OFFSET

0,2


COMMENTS

The implication is that 10...01, 10...02, 10...03, ..., 10...024 are never cubes for any number of internal zeros, while 125 IS a cube, so a(2) = 25.  N. J. A. Sloane, Jul 21 2001


REFERENCES

Amarnath Murthy, Exploring some new ideas on Smarandache type sets, functions and sequences, Smarandache Notions Journal Vol. 11, No. 123, Spring 2000.


LINKS

Table of n, a(n) for n=0..3.


EXAMPLE

a(1) = 1, a(1)a(2) = 125 = 5^3, a(1)a(2)a(3) = 1259712 = 108^3, a(1)a(2)a(3)0a(4) = 5012916^3.


CROSSREFS

Cf. A061109, A051671, A061110.
Sequence in context: A306380 A053860 A091744 * A238564 A195682 A082211
Adjacent sequences: A061108 A061109 A061110 * A061112 A061113 A061114


KEYWORD

base,nonn


AUTHOR

Amarnath Murthy, Apr 20 2001


STATUS

approved



