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a(n) in base 15 is a repdigit.
2

%I #24 May 30 2016 18:26:26

%S 0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,16,32,48,64,80,96,112,128,144,160,

%T 176,192,208,224,241,482,723,964,1205,1446,1687,1928,2169,2410,2651,

%U 2892,3133,3374,3616,7232,10848,14464,18080,21696,25312,28928,32544

%N a(n) in base 15 is a repdigit.

%H Vincenzo Librandi, <a href="/A048339/b048339.txt">Table of n, a(n) for n = 0..700</a>

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

%F From _Chai Wah Wu_, May 30 2016: (Start)

%F a(n) = 16*a(n-14) - 15*a(n-28) for n > 27.

%F G.f.: x*(14*x^13 + 13*x^12 + 12*x^11 + 11*x^10 + 10*x^9 + 9*x^8 + 8*x^7 + 7*x^6 + 6*x^5 + 5*x^4 + 4*x^3 + 3*x^2 + 2*x + 1)/(15*x^28 - 16*x^14 + 1). (End)

%F a(n) = (n - 14*floor((n-1)/14))*(15^floor((n+13)/14) - 1)/14. - _Ilya Gutkovskiy_, May 30 2016

%t Union[Flatten[Table[FromDigits[PadRight[{}, n, d], 15], {n, 0, 5}, {d, 14}]]] (* _Harvey P. Dale_, Feb 05 2014 *)

%o (Python)

%o A048339_list = [0] + [int(d*l,15) for l in range(1,10) for d in '123456789abcde'] # _Chai Wah Wu_, May 30 2016

%Y Cf. A010785, A033028, A028987, A028988.

%K nonn,base,easy

%O 0,3

%A _Patrick De Geest_, Feb 15 1999