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%I #16 Jan 02 2023 15:46:20
%S 4,28,172,1036,6220,37324,223948,1343692,8062156,48372940,290237644,
%T 1741425868,10448555212,62691331276,376147987660,2256887925964,
%U 13541327555788,81247965334732,487487792008396,2924926752050380,17549560512302284,105297363073813708
%N The base 6 numbers 4 44 444 4444 44444 ... converted to base 10.
%H Harvey P. Dale, <a href="/A125687/b125687.txt">Table of n, a(n) for n = 1..1000</a>
%H <a href="/index/Rec#order_02">Index entries for linear recurrences with constant coefficients</a>, signature (7,-6).
%F a(n) = (6^n-1)*4/5.
%F G.f.: 4*x/((1-x)*(1-6*x)). - _Vincenzo Librandi_, Sep 26 2015
%e Base 6.........decimal
%e 4....................4
%e 44..................28
%e 444................172
%e 4444..............1036
%e 44444.............6220
%e 444444...........37324
%e 4444444.........223948
%e 44444444.......1343692
%e 444444444......8062156
%e 4444444444....48372940
%e etc.
%p seq((6^n-1)*4/5, n=1..24);
%t 4 (6^Range[20]-1)/5 (* _Harvey P. Dale_, Mar 12 2011 *)
%t Rest[CoefficientList[Series[4 x/((1 - x) (1 - 6 x)), {x, 0, 30}], x]] (* _Vincenzo Librandi_, Sep 26 2015 *)
%t Table[FromDigits[PadRight[{},n,4],6],{n,30}] (* or *) LinearRecurrence[{7,-6},{4,28},30] (* _Harvey P. Dale_, Jan 02 2023 *)
%o (Magma) [(6^n-1)*4/5: n in [1.. 35]]; // _Vincenzo Librandi_, Sep 26 2015
%K easy,nonn
%O 1,1
%A _Zerinvary Lajos_, Jan 31 2007
%E Edited by _N. J. A. Sloane_, Feb 02 2007
%E More terms from _Vincenzo Librandi_, Sep 26 2015
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