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A039685
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Numbers n such that n^2 ends in 444.
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1
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38, 462, 538, 962, 1038, 1462, 1538, 1962, 2038, 2462, 2538, 2962, 3038, 3462, 3538, 3962, 4038, 4462, 4538, 4962, 5038, 5462, 5538, 5962, 6038, 6462, 6538, 6962, 7038, 7462, 7538, 7962, 8038, 8462, 8538, 8962, 9038, 9462, 9538, 9962, 10038, 10462
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,1
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COMMENTS
| No square can end in more than three 4's.
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REFERENCES
| Albert H. Beiler, "Recreations in the Theory of Numbers", Dover Publ., 2nd Ed. 1966, Chapter XV, "On The Square", p. 139. ISBN 0-486-21096-0.
David Wells, "Curious and Interesting Numbers", Revised Ed. Penguin Books, p. 152. ISBN 0-14-026149-4.
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LINKS
| Index to sequences with linear recurrences with constant coefficients, signature (1,1,-1). [From Bruno Berselli (berselli.bruno(AT)yahoo.it), Oct 27 2010]
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FORMULA
| a(2n+1)=500n+38 and a(2n+2)=500n-38.
Contribution from Bruno Berselli (berselli.bruno(AT)yahoo.it), Oct 27 2010: (Start)
a(n) = 250*n+87*(-1)^n-125.
G.f.: 2*x*(19+212*x+19*x^2)/((1+x)*(1-x)^2).
a(n)-a(n-1)-a(n-2)+a(n-3)=0 for n>3. (End)
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MATHEMATICA
| Drop[ Flatten[ Table[{500n-38, 500n+38}, {n, 0, 21}]], 1] (from Robert G. Wilson v Nov 27 2004)
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CROSSREFS
| Sequence in context: A187078 A155193 A159943 * A006418 A160317 A088891
Adjacent sequences: A039682 A039683 A039684 * A039686 A039687 A039688
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KEYWORD
| nonn,base
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AUTHOR
| Felice Russo (frusso(AT)micron.com)
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EXTENSIONS
| More terms from Patrick De Geest (pdg(AT)worldofnumbers.com), Jun 15 1999.
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