A115589 - OEIS

%I #9 Jan 12 2015 03:47:32

%S 1,7,49,28,63,14,56,42,21,7,28,35,42,28,14,14,7,49,14,56,21,35,28,14,

%T 14,56,7,28,7,28,49,28,63,7,28,35,42,14,7,21,35,14,56,7,28,7,28,35,42,

%U 49,14,56,49,14,56,28,63,14,56,42,21,49,14,56,21,35,28,14,7,28,49,14,7,21

%N Multiply first digit by k, append result to sequence; multiply second digit by k, append result to sequence; multiply third digit by k, append result to sequence; etc. a(1)=1, k=7 case.

%C All terms are evidently multiples of 7: 7, 14, ..., 63. Is the sequence periodic? Some repeating patterns are obvious, e.g., 63, 7, 28, 35, 42, but no cycle appears.

%t ss=s={1};Do[d=7s[[i]];AppendTo[ss,d];s=Flatten[{s,IntegerDigits[d]}],{i,200}];ss

%Y Cf. A115425.

%K nonn,base

%O 1,2

%A _Zak Seidov_, Mar 09 2006