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A153435
Numbers with 2n binary digits where every run length is 2, written in binary.
8
11, 1100, 110011, 11001100, 1100110011, 110011001100, 11001100110011, 1100110011001100, 110011001100110011, 11001100110011001100, 1100110011001100110011, 110011001100110011001100
OFFSET
1,1
COMMENTS
A043291 written in base 2.
FORMULA
From Colin Barker, Apr 19 2014: (Start)
a(n) = (-101-99*(-1)^n+2^(3+2*n)*25^(1+n))/1818.
a(n) = 100*a(n-1)+a(n-2)-100*a(n-3).
G.f.: 11*x / ((x-1)*(x+1)*(100*x-1)).(End).
EXAMPLE
n ... a(n) ....... A043291(n)
1 ... 11 ............. 3
2 ... 1100 .......... 12
3 ... 110011 ........ 51
4 ... 11001100 ..... 204
5 ... 1100110011 ... 819
MAPLE
A153435:=n->(-101-99*(-1)^n+2^(3+2*n)*25^(1+n))/1818; seq(A153435(n), n=1..20); # Wesley Ivan Hurt, Apr 19 2014
MATHEMATICA
Table[(-101 - 99*(-1)^n + 2^(3 + 2*n)*25^(1 + n))/1818, {n, 20}] (* Wesley Ivan Hurt, Apr 19 2014 *)
CoefficientList[Series[11/((x - 1) (x + 1) (100 x - 1)), {x, 0, 30}], x] (* Vincenzo Librandi, Apr 20 2014 *)
PROG
(PARI) Vec(11*x / ((x-1)*(x+1)*(100*x-1)) + O(x^100)) \\ Colin Barker, Apr 19 2014
CROSSREFS
Cf. A043291.
Sequence in context: A347846 A319424 A348269 * A266787 A109227 A133342
KEYWORD
easy,nonn,base
AUTHOR
Omar E. Pol, Dec 26 2008
STATUS
approved