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A163664
a(n) = 10^(2*n) + 10^n.
4
110, 10100, 1001000, 100010000, 10000100000, 1000001000000, 100000010000000, 10000000100000000, 1000000001000000000, 100000000010000000000, 10000000000100000000000, 1000000000001000000000000, 100000000000010000000000000, 10000000000000100000000000000
OFFSET
1,1
COMMENTS
A161168(n) or A063376(n) for n >= 1 written in base 2.
The digits from the left to the right: a 1, (n-1) times 0, a 1, and n times 0.
FORMULA
a(n) = 110*a(n-1) - 1000*a(n-2).
a(n) = 10*A163449(n).
G.f.: 10*x*(11 -200*x)/((100*x-1)*(10*x-1)).
E.g.f.: exp(100*x) + exp(10*x) -2. - G. C. Greubel, Aug 01 2017
MATHEMATICA
LinearRecurrence[{110, -1000}, {110, 10100}, 50] (* G. C. Greubel, Aug 01 2017 *)
PROG
(PARI) x='x+O('x^50); Vec(10*x*(11 -200*x)/((100*x-1)*(10*x-1))) \\ G. C. Greubel, Aug 01 2017
CROSSREFS
Sequence in context: A146495 A063751 A266179 * A266844 A265319 A267854
KEYWORD
nonn,base,easy
AUTHOR
Jaroslav Krizek, Aug 02 2009
EXTENSIONS
Edited by R. J. Mathar, Aug 06 2009
STATUS
approved