[seqfan] nice base-dependent sequence

N. J. A. Sloane njas at research.att.com
Fri May 28 18:10:54 CEST 2010

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.


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