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A158407
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a(n) = 900*n + 1.
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2
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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
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OFFSET
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1,1
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COMMENTS
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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
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FORMULA
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MATHEMATICA
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PROG
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(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
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CROSSREFS
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KEYWORD
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nonn,easy
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AUTHOR
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STATUS
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approved
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