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A120202
a(n) = ceiling( Sum_{i=1..n-1} a(i)/9), a(1)=1.
10
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2, 3, 3, 3, 4, 4, 5, 5, 6, 6, 7, 8, 9, 10, 11, 12, 13, 15, 16, 18, 20, 22, 25, 28, 31, 34, 38, 42, 47, 52, 58, 64, 71, 79, 88, 98, 109, 121, 134, 149, 166, 184, 205, 227, 253, 281, 312, 347, 385, 428, 476, 528, 587, 652, 725, 805, 895
OFFSET
1,11
LINKS
MAPLE
N:= 100: # to get a(1) to a(N)
S:= 0: A[1]:= 1:
for n from 2 to N do
S:= S + A[n-1];
A[n]:= ceil(S/9);
od:
seq(A[n], n=1..N); # Robert Israel, Jul 14 2014
MATHEMATICA
a[s_] := Append[s, Ceiling[Plus @@ s/9]]; Nest[a, {1}, 70] (* Robert G. Wilson v, Jul 07 2006 *)
KEYWORD
nonn
AUTHOR
Graeme McRae, Jun 10 2006
EXTENSIONS
Edited and extended by Robert G. Wilson v, Jul 07 2006
Typo in name corrected by Tom Edgar, Jul 14 2014
STATUS
approved