The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A048329 a(n) in base 4 is a repdigit. 5

%I

%S 0,1,2,3,5,10,15,21,42,63,85,170,255,341,682,1023,1365,2730,4095,5461,

%T 10922,16383,21845,43690,65535,87381,174762,262143,349525,699050,

%U 1048575,1398101,2796202,4194303,5592405,11184810,16777215,22369621

%N a(n) in base 4 is a repdigit.

%H Vincenzo Librandi, <a href="/A048329/b048329.txt">Table of n, a(n) for n = 0..300</a>

%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/Repdigit.html">Repdigit</a>

%H <a href="/index/Rec#order_06">Index entries for linear recurrences with constant coefficients</a>, signature (0,0,5,0,0,-4).

%F G.f.: x*(1+2*x+3*x^2) / ( (x-1)*(4*x^3-1)*(1+x+x^2) ) with a(n) = 5*a(n-3) - 4*a(n-6). - _R. J. Mathar_, Mar 15 2015

%e 10_10 = 22_4, 15_10 = 33_4, 5461_10 = 1111111_4.

%t Union[Flatten[Table[FromDigits[PadRight[{}, n, d], 4], {n, 0, 40}, {d, 3}]]](* _Vincenzo Librandi_, Feb 06 2014 *)

%o (MAGMA) [0] cat [k:k in [1..10^7]| #Set(Intseq(k,4)) eq 1]; // _Marius A. Burtea_, Oct 11 2019

%Y Cf. A010785, A033017, A028987, A028988.

%Y Base 4 repdigits 1,2,3 (trisections): A002450, A020988, A024036.

%K nonn,base

%O 0,3

%A _Patrick De Geest_, Feb 15 1999

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified April 17 06:46 EDT 2021. Contains 343059 sequences. (Running on oeis4.)