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A093135
Expansion of (1-8*x)/((1-x)*(1-10*x)).
2
1, 3, 23, 223, 2223, 22223, 222223, 2222223, 22222223, 222222223, 2222222223, 22222222223, 222222222223, 2222222222223, 22222222222223, 222222222222223, 2222222222222223, 22222222222222223, 222222222222222223
OFFSET
0,2
COMMENTS
Second binomial transform of 2*A001045(3n)/3+(-1)^n. Partial sums of A093136. A convex combination of 10^n and 1. In general the second binomial transform of k*Jacobsthal(3n)/3+(-1)^n is 1,1+k,1+11k,1+111k,... This is the case for k=2.
Essentially the same as A091628 (cf. 2nd formula). - Georg Fischer, Oct 06 2018
a(n) is 3^n represented in bijective base-3 numeration. - Alois P. Heinz, Aug 26 2019
FORMULA
a(n) = 2*10^n/9 + 7/9.
a(n) = 10*a(n-1) - 7 (with a(0)=1). - Vincenzo Librandi, Aug 02 2010
CROSSREFS
Sequence in context: A114017 A316085 A068691 * A305754 A202997 A093162
KEYWORD
nonn,easy
AUTHOR
Paul Barry, Mar 24 2004
STATUS
approved