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A083811
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Numbers n such that 2n+1 is the digit reversal of n+1.
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5
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36, 396, 3996, 39996, 399996, 3999996, 39999996, 399999996, 3999999996, 39999999996, 399999999996, 3999999999996
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OFFSET
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1,1
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COMMENTS
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1. a(n) = 36 + 360 + 3600+ ...+ up to n terms. a(n) = sum of n terms of the geometric progression with the first term 36 and common ratio 10. 2. a(n) = 36*A000042(n).( the unary sequence).
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LINKS
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FORMULA
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a(n) = 4*(10^n - 1).
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EXAMPLE
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36 + 1 = 37, 2*36 + 1 = 73.
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CROSSREFS
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KEYWORD
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base,nonn
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AUTHOR
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Amarnath Murthy and Meenakshi Srikanth (menakan_s(AT)yahoo.com), May 08 2003
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STATUS
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approved
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