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%I #24 Jan 02 2023 12:30:47
%S 0,11,40,87,152,235,336,455,592,747,920,1111,1320,1547,1792,2055,2336,
%T 2635,2952,3287,3640,4011,4400,4807,5232,5675,6136,6615,7112,7627,
%U 8160,8711,9280,9867,10472,11095,11736,12395,13072,13767,14480,15211,15960
%N a(n) = n*(9*n+2).
%C For n >= 1, the continued fraction expansion of sqrt(4*a(n)) is [6n; {1, 1, 1, 3n-1, 1, 1, 1, 12n}]. - _Magus K. Chu_, Sep 17 2022
%H Reply to V. Librandi, <a href="http://list.seqfan.eu/oldermail/seqfan/2009-March/001017.html">A147296 (SeqFan list)</a> - _M. F. Hasler_, Mar 01 2009
%H <a href="/index/Rec#order_03">Index entries for linear recurrences with constant coefficients</a>, signature (3, -3, 1).
%F a(n) = n*(9*n + 2), as conjectured by V. Librandi. - From M. F. Hasler, Mar 01 2009
%F G.f.: x*(11+7*x)/(1-x)^3. - Jaume Oliver Lafont, Aug 30 2009
%F a(n) = floor((3*n + 1/3)^2). - _Reinhard Zumkeller_, Apr 14 2010
%t Table[n(9n+2),{n,0,50}] (* or *) LinearRecurrence[{3,-3,1},{0,11,40},50] (* _Harvey P. Dale_, Dec 19 2014 *)
%o (PARI) A147296(n) = n*(9*n + 2) - _M. F. Hasler_, Mar 01 2009
%Y Equals first 9-fold decimation of A144454.
%Y Cf. A010701, A017173, A185019.
%K nonn,easy
%O 0,2
%A _Paul Curtz_, Nov 05 2008
%E More terms from _M. F. Hasler_, Mar 01 2009
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