Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).
%I #14 Feb 18 2024 08:27:25
%S 10,11100,11111000,11111110000,11111111100000,11111111111000000,
%T 11111111111110000000,11111111111111100000000,
%U 11111111111111111000000000,11111111111111111110000000000
%N Concatenation of 2n-1 digits 1 and n digits 0.
%C a(n) is also A147537(n) written in base 2. [From _Omar E. Pol_, Nov 08 2008]
%H <a href="/index/Rec#order_02">Index entries for linear recurrences with constant coefficients</a>, signature (1010,-10000)
%F O.g.f.: 10*(1+100x)/[(-1+1000x)*(-1+10x)]. a(n)=A100706(n)*10^n = 10*a(n-1)+11*1000^n. - _R. J. Mathar_, Apr 03 2008
%e n .......... a(n)
%e 1 ........... 10
%e 2 ......... 11100
%e 3 ....... 11111000
%e 4 ..... 11111110000
%e 5 ... 11111111100000
%t FromDigits/@Table[Join[PadRight[{},2n-1,1],PadRight[{},n,0]],{n,15}] (* _Harvey P. Dale_, Dec 09 2011 *)
%Y Cf. A138147, A138721.
%Y Cf. A147537.
%K easy,nonn,base
%O 1,1
%A _Omar E. Pol_, Mar 29 2008