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30, 138, 318, 570, 894, 1290, 1758, 2298, 2910, 3594, 4350, 5178, 6078, 7050, 8094, 9210, 10398, 11658, 12990, 14394, 15870, 17418, 19038, 20730, 22494, 24330, 26238, 28218, 30270, 32394, 34590, 36858, 39198, 41610, 44094, 46650, 49278, 51978
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,1
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COMMENTS
| The identity (12*n^2-1)^2-(36*n^2-6)*(2*n)^2 = 1 can be written as A158463(n)^2-a(n)*A005843(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
| G.f.: 6*x*(5+8*x-x^2)/(1-x)^3. - Bruno Berselli, Aug 27 2011
a(n) = 3*a(n-1) -3*a(n-2) +a(n-3). - Vincenzo Librandi, Feb 12 2012
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MATHEMATICA
| LinearRecurrence[{3, -3, 1}, {30, 138, 318}, 50] (* Vincenzo Librandi, Feb 12 2012 *)
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PROG
| (MAGMA) I:=[30, 138, 318]; [n le 3 select I[n] else 3*Self(n-1)-3*Self(n-2)+1*Self(n-3): n in [1..50]]; // Vincenzo Librandi, Feb 12 2012
(PARI) for(n=1, 40, print1(36*n^2-6", ")); \\ Vincenzo Librandi, Feb 12 2012
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CROSSREFS
| Cf. A005843, A158463.
Sequence in context: A100147 A079588 A117750 * A064495 A124958 A126417
Adjacent sequences: A158459 A158460 A158461 * A158463 A158464 A158465
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KEYWORD
| nonn,easy,changed
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AUTHOR
| Vincenzo Librandi (vincenzo.librandi(AT)tin.it), Mar 19 2009
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