OFFSET
0,3
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 0..1000
Eric Weisstein's World of Mathematics, Repdigit
FORMULA
From Chai Wah Wu, May 30 2016: (Start)
a(n) = 12*a(n-10) - 11*a(n-20) for n > 19.
G.f.: x*(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)/(11*x^20 - 12*x^10 + 1). (End)
a(n) = (n - 10*floor((n-1)/10))*(11^floor((n+9)/10) - 1)/10. - Ilya Gutkovskiy, May 30 2016
MATHEMATICA
Union[Flatten[Table[FromDigits[PadRight[{}, n, d], 11], {n, 0, 50}, {d, 10}]]] (* Vincenzo Librandi, Feb 06 2014 *)
PROG
(Python)
A048335_list = [0] + [int(d*l, 11) for l in range(1, 10) for d in '123456789a'] # Chai Wah Wu, May 30 2016
CROSSREFS
KEYWORD
nonn,base,easy
AUTHOR
Patrick De Geest, Feb 15 1999
STATUS
approved