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10, 38, 84, 148, 230, 330, 448, 584, 738, 910, 1100, 1308, 1534, 1778, 2040, 2320, 2618, 2934, 3268, 3620, 3990, 4378, 4784, 5208, 5650, 6110, 6588, 7084, 7598, 8130, 8680, 9248, 9834, 10438, 11060, 11700, 12358, 13034, 13728, 14440
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,1
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COMMENTS
| The identity (648*n^2+72*n+1)^2-(9*n^2+n)*(216*n+12)^2=1 can be written as A154515(n)^2-a(n)*A154519(n)^2=1 (see also the second comment in A154515). - Vincenzo Librandi, Jan 31 2012
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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.: x*(-10-8*x)/(x-1)^3. - Vincenzo Librandi, Jan 31 2012
a(n) = 3*a(n-1) -3*a(n-2) +a(n-3). - Vincenzo Librandi, Jan 31 2012
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MATHEMATICA
| LinearRecurrence[{3, -3, 1}, {10, 38, 84}, 50] (* Vincenzo Librandi, Jan 31 2012 *)
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PROG
| (PARI) a(n)=9*n^2+n \\ Charles R Greathouse IV, Dec 27 2011
(MAGMA) I:=[10, 38, 84]; [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, Jan 31 2012
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CROSSREFS
| Cf. A154515, A154519.
Sequence in context: A129426 A065009 A031430 * A034859 A197060 A136840
Adjacent sequences: A154514 A154515 A154516 * A154518 A154519 A154520
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KEYWORD
| nonn,easy
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AUTHOR
| Vincenzo Librandi (vincenzo.librandi(AT)tin.it), Jan 11 2009
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