A152764 Bisection of A138144.

1, 111, 11011, 1100011, 110000011, 11000000011, 1100000000011, 110000000000011, 11000000000000011, 1100000000000000011, 110000000000000000011, 11000000000000000000011

Offset

1,2

Links

Table of n, a(n) for n=1..12.

Index entries for linear recurrences with constant coefficients, signature (101,-100).

Formula

From Colin Barker, Sep 16 2013: (Start)

a(n) = 11+11*10^(2*n-3) for n>2.

a(n) = 101*a(n-1)-100*a(n-2) for n>4.

G.f.: -x*(10*x-1)*(10*x+1)^2 / ((x-1)*(100*x-1)). (End)

Example

n ...... a(n)
1 ....... 1
2 ...... 111
3 ..... 11011
4 .... 1100011
5 ... 110000011

Mathematica

LinearRecurrence[{101, -100}, {1, 111, 11011, 1100011}, 20] (* Harvey P. Dale, Nov 26 2019 *)

Prog

(PARI) Vec(-x*(10*x-1)*(10*x+1)^2/((x-1)*(100*x-1)) + O(x^100)) \\ Colin Barker, Sep 16 2013

Crossrefs

Cf. A135577, A138120, A138146, A152756, A152758, A058764.

Sequence in context: A353112 A245549 A266809 * A249183 A071033 A267364

Adjacent sequences: A152761 A152762 A152763 * A152765 A152766 A152767

Keyword

easy,nonn,base

Author

Omar E. Pol, Dec 14 2008

Status

approved