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901, 1801, 2701, 3601, 4501, 5401, 6301, 7201, 8101, 9001, 9901, 10801, 11701, 12601, 13501, 14401, 15301, 16201, 17101, 18001, 18901, 19801, 20701, 21601, 22501, 23401, 24301, 25201, 26101, 27001, 27901, 28801, 29701, 30601, 31501
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,1
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COMMENTS
| The identity (900*n+1)^2-(900*n^2+2*n)*(30)^2 = 1 can be written as a(n)^2-A158406(n)*(30)^2 = 1. - Vincenzo Librandi, Feb 09 2012
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LINKS
| Vincenzo Librandi, Table of n, a(n) for n = 1..10000
Vincenzo Librandi, X^2-AY^2=1
Index to sequences with linear recurrences with constant coefficients, signature (2,-1).
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FORMULA
| G.f.: x*(901-x)/(1-x)^2. - Vincenzo Librandi, Feb 09 2012
a(n) = 2*a(n-1)-a(n-2). - Vincenzo Librandi, Feb 09 2012
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MATHEMATICA
| LinearRecurrence[{2, -1}, {901, 1801}, 50] (* Vincenzo Librandi, Feb 09 2012 *)
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PROG
| (MAGMA) I:=[901, 1801]; [n le 2 select I[n] else 2*Self(n-1)-Self(n-2): n in [1..50]]; // Vincenzo Librandi, Feb 09 2012
(PARI) for(n=1, 40, print1(900*n + 1", ")); \\ Vincenzo Librandi, Feb 09 2012
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CROSSREFS
| Cf. A158406.
Sequence in context: A093798 A093218 A093215 * A031738 A031618 A031528
Adjacent sequences: A158404 A158405 A158406 * A158408 A158409 A158410
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KEYWORD
| nonn,easy,changed
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AUTHOR
| Vincenzo Librandi (vincenzo.librandi(AT)tin.it), Mar 18 2009
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