

A077189


Smallest concatenation 123...(k1) k (k1)...321 (a concatenation of natural numbers from 1 to k and back to 1) that is a multiple of 2n1, or 0 if no such number exists.


3




OFFSET

1,2


COMMENTS

a(5k+3) = 0. Are there any other values of n such that a(n) = 0?
The next value, 2n1 = 17, has k = 109, for a total of 435 digits and is too large to include.  Franklin T. AdamsWatters, Jun 02 2006


LINKS

Jinyuan Wang, Table of n, a(n) for n = 1..11


EXAMPLE

a(5) = 12321 is a multiple of 9.


CROSSREFS

Cf. A077180, A077181, A077182, A077183, A077184, A077186, A077188, A077190.
Cf. A120008.
Sequence in context: A250856 A242716 A077186 * A277947 A321492 A237782
Adjacent sequences: A077186 A077187 A077188 * A077190 A077191 A077192


KEYWORD

nonn,base


AUTHOR

Amarnath Murthy, Nov 01 2002


EXTENSIONS

More terms from Franklin T. AdamsWatters, Jun 02 2006


STATUS

approved



