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A063945 - OEIS
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A063945
Number of nonnegative integers with n digits.
4
10, 90, 900, 9000, 90000, 900000, 9000000, 90000000, 900000000, 9000000000, 90000000000, 900000000000, 9000000000000, 90000000000000, 900000000000000, 9000000000000000, 90000000000000000, 900000000000000000, 9000000000000000000, 90000000000000000000
OFFSET
1,1
COMMENTS
Also, first differences of A000533. - Omar E. Pol, Feb 24 2011
FORMULA
a(1) = 10, a(2) = 90, a(n) = a(n-1)*10 for n>2.
a(n) = A052268(n), n>1. - R. J. Mathar, Oct 02 2008
MAPLE
a:= n-> `if`(n=1, 10, 9*10^(n-1)):
seq(a(n), n=1..30); # Alois P. Heinz, Sep 12 2012
MATHEMATICA
Join[{10}, NestList[10#&, 90, 20]] (* Harvey P. Dale, Dec 31 2022 *)
CROSSREFS
Column k=1 of A216653.
Sequence in context: A137684 A097394 A172199 * A218127 A322647 A243106
KEYWORD
base,easy,nonn
AUTHOR
Shyam Sunder Gupta, Sep 01 2001
STATUS
approved