[seqfan] Re: nice base-dependent sequence

Jonathan Post jvospost3 at gmail.com
Fri May 28 18:43:17 CEST 2010


I like it too.  But so long as someone's programming it, why not do so
base j for bases other than 10, and show us the upper left corner of
the array
A[j,n] = n-th smallest integer k such that k or one of its substrings
(base j) is divisible by every integer in {1, 2, ..., n}?

Jonathan Vos Post

On Fri, May 28, 2010 at 9:10 AM, N. J. A. Sloane <njas at research.att.com> wrote:
> Dear Seq Fans,  This just caught my eye.  Anyone care to
> produce a b-file?
>
> %I A177834
> %S A177834 1,2,6,12,45,54,56,56,245,504,1440,1440,5044,5044,10456,10569,11704,
> %T A177834 11704,11704,13608,13608,13608,26460,26460,198007,258064,264600,264600,
> %U A177834 475440,475440,1754608,1754608,2258064,2258064,2646004,2646004,2992520
> %N A177834 Smallest integer k such that k or one of its substrings (regarded as an integer) is divisible by every integer from {1,2,...,n}
> %e A177834 a(8)=56 because 56 is divisible by 1,2,4,7,8; 5 is divisible by 5; 6 is divisible by 3 and 6. Therefore the set {1,2,3,4,5,6,7,8} is covered by the divisors. 56 is the smallest number with this property.
> %K A177834 nonn,base,nice,new
> %O A177834 1,2
> %A A177834 Martins Opmanis (askola(AT)latnet.lv), May 14 2010
> %E A177834 Edited by N. J. A. Sloane, May 28 2010.
>
> Neil
>
>
>
> _______________________________________________
>
> Seqfan Mailing list - http://list.seqfan.eu/
>




More information about the SeqFan mailing list