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47, 192, 435, 776, 1215, 1752, 2387, 3120, 3951, 4880, 5907, 7032, 8255, 9576, 10995, 12512, 14127, 15840, 17651, 19560, 21567, 23672, 25875, 28176, 30575, 33072, 35667, 38360, 41151, 44040, 47027, 50112, 53295, 56576, 59955, 63432, 67007
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,1
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COMMENTS
| The identity (4802*n^2-196*n+1)^2-(49*n^2-2*n)*(686*n-14)^2=1 can be written as A157364(n)^2-a(n)*A157363(n)^2=1.
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LINKS
| Vincenzo Librandi, Table of n, a(n) for n = 1..10000
Index to sequences with linear recurrences with constant coefficients, signature (3,-3,1).
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FORMULA
| a(n) = 3*a(n-1) -3*a(n-2) +a(n-3).
G.f.: x*(47+51*x)/(1-x)^3.
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MATHEMATICA
| LinearRecurrence[{3, -3, 1}, {47, 192, 435}, 50]
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PROG
| (MAGMA) I:=[47, 192, 435]; [n le 3 select I[n] else 3*Self(n-1)-3*Self(n-2)+1*Self(n-3): n in [1..40]];
(PARI) a(n)=49*n^2-2*n \\ Charles R Greathouse IV, Dec 23 2011
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CROSSREFS
| Cf. A157363, A157364.
Sequence in context: A158632 A142413 A065532 * A141874 A142203 A067986
Adjacent sequences: A157359 A157360 A157361 * A157363 A157364 A157365
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KEYWORD
| nonn,easy,changed
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AUTHOR
| Vincenzo Librandi (vincenzo.librandi(AT)tin.it), Feb 28 2009
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