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Search: id:A095761
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| A095761 |
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Numbers whose square root shows strings of seemingly rational and irrational strings. |
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+0
1
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| 1, 123, 12345, 1234567, 123456789, 12345679011, 1234567901233, 123456790123455, 12345679012345677, 1234567901234567899, 123456790123456790121, 12345679012345679012343
(list; graph; listen)
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OFFSET
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1,2
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COMMENT
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Definition not clear to me - more information please! - N. J. A. Sloane (njas(AT)research.att.com), Jul 11 2004
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REFERENCES
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Related to A014824.
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LINKS
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K. S. Brown, Schizophrenic numbers
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FORMULA
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a(1) = 1; for n > 1, a(n) = 100*a(n - 1) + 22*n - 21.
O.g.f.: x(1+21x)/[(-1+x)^2*(1-100x)] = -17/[81(-1+x)]-1/[81(-1+100*x)]-2/[9(-1+x)^2] . - R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Feb 01 2008
a(n)=-(19/81)-(2/9)*(n-1)+(100/81)*100^(n-1), with n>=1 [From Paolo P. Lava (ppl(AT)spl.at), Sep 26 2008]
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EXAMPLE
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a(6) = 100*a(5) + 22*6 - 21 = 100*123456789 + 132 - 21 = 12345679011.
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CROSSREFS
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Sequence in context: A068239 A098683 A135479 this_sequence A121917 A049670 A033522
Adjacent sequences: A095758 A095759 A095760 this_sequence A095762 A095763 A095764
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KEYWORD
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easy,nonn,base,obsc
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AUTHOR
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Michael Joseph Halm (hierogamous(AT)lycos.com), Jul 10 2004
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