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A232229
a(1)=9; thereafter a(n) = 8*10^(n-1) + 8 + a(n-1).
1
9, 97, 905, 8913, 88921, 888929, 8888937, 88888945, 888888953, 8888888961, 88888888969, 888888888977, 8888888888985, 88888888888993, 888888888889001, 8888888888889009, 88888888888889017, 888888888888889025, 8888888888888889033, 88888888888888889041, 888888888888888889049, 8888888888888888889057
OFFSET
1,1
COMMENTS
An infinite subsequence of A003052.
FORMULA
G.f.: x*(-9+11*x+70*x^2) / ( (10*x-1)*(x-1)^2 ). a(n) = (8*10^n-71)/9+8*n. - R. J. Mathar, Nov 24 2013
MAPLE
f:=proc(n) option remember; if n=1 then 9 else
8*10^(n-1)+8+f(n-1); fi; end;
[seq(f(n), n=1..40)];
MATHEMATICA
RecurrenceTable[{a[1]==9, a[n]==8*10^(n-1)+8+a[n-1]}, a, {n, 30}] (* Harvey P. Dale, May 19 2018 *)
CROSSREFS
Sequence in context: A069636 A069621 A284668 * A240780 A236672 A155699
KEYWORD
nonn,easy
AUTHOR
N. J. A. Sloane, Nov 22 2013
EXTENSIONS
Definition corrected by Harvey P. Dale, May 19 2018
STATUS
approved