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A050684
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Number of nonzero palindromes < 10^n and containing at least one digit '1'.
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1
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1, 2, 20, 38, 290, 542, 3710, 6878, 44390, 81902, 509510, 937118, 5685590, 10434062, 62170310, 113906558, 669532790, 1225159022, 7125795110, 13026431198, 75132155990, 137237880782, 786189403910, 1435140927038
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,2
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FORMULA
| a(2n) = 2*(10^n - 9^n); a(2n + 1) = 2*(10^n - 9^n) + 9*10^n - 8*9^n. - David Wasserman (wasserma(AT)spawar.navy.mil), Feb 14 2002
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EXAMPLE
| Up to 10^2 we find two numbers 1 and 11.
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CROSSREFS
| Cf. A050250, A050685.
Sequence in context: A201122 A103076 A062133 * A073214 A194999 A202602
Adjacent sequences: A050681 A050682 A050683 * A050685 A050686 A050687
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KEYWORD
| nonn,base
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AUTHOR
| Patrick De Geest (pdg(AT)worldofnumbers.com), Aug 15 1999.
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EXTENSIONS
| More terms from David Wasserman (wasserma(AT)spawar.navy.mil), Feb 14 2002
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