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1, 2, 20, 272, 3440, 40952, 468560, 5217032, 56953280, 612579512, 6513215600, 68618940392, 717570463520, 7458134171672, 77123207545040, 794108867905352, 8146979811148160, 83322818300333432, 849905364703000880
(list; graph; refs; listen; history; internal format)
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OFFSET
| 0,2
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COMMENTS
| a(n) is the number of numbers from 1 to 10^n containing a 1 in their decimal expansion. - Charles R Greathouse IV, Mar 25 2009
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LINKS
| Index entries for sequences related to linear recurrences with constant coefficients, signature (20,-109,90).
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FORMULA
| G.f.: 1/(1-10*x)-1/(1-9*x)+1/(1-x). E.g.f.: e^(10*x)-e^(9*x)+e^x.
a(n)=19*a(n-1)-90*a(n-2)+72 with a(0)=1, a(1)=2 [From Vincenzo Librandi (vincenzo.librandi(AT)tin.it), Jul 21 2010]
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CROSSREFS
| Equals A016189 + 1. See that entry for more information.
Cf. A155654, A155655, A155656, A155657, A155658, A155659, A155660, A155661, A155662, A155663, A155664, A155665, A155666, A155667, A155668, A155669, A155670
Sequence in context: A099976 A195157 A207151 * A124211 A128481 A177397
Adjacent sequences: A155668 A155669 A155670 * A155672 A155673 A155674
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KEYWORD
| nonn,easy
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AUTHOR
| Mohammad K. Azarian (azarian(AT)evansville.edu), Feb 01 2009
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