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%I #17 Jun 18 2017 12:38:58
%S 0,10,60,150,280,450,660,910,1200,1530,1900,2310,2760,3250,3780,4350,
%T 4960,5610,6300,7030,7800,8610,9460,10350,11280,12250,13260,14310,
%U 15400,16530,17700,18910,20160,21450,22780,24150,25560,27010
%N Ten times hexagonal numbers: 10*n*(2*n-1).
%C Sequence found by reading the line from 0, in the direction 0, 10,..., in the square spiral whose vertices are the generalized dodecagonal numbers A195162. - _Omar E. Pol_, Sep 18 2011
%H Ivan Panchenko, <a href="/A144560/b144560.txt">Table of n, a(n) for n = 0..1000</a>
%H <a href="/index/Rec#order_03">Index entries for linear recurrences with constant coefficients</a>, signature (3,-3,1).
%F a(n) = 20n^2 - 10n = A000384(n)*10 = A002939(n)*5 = A152745(n)*2.
%F a(n) = a(n-1)+40*n-30 (with a(0)=0). - _Vincenzo Librandi_, Dec 14 2010
%o (PARI) a(n)=10*n*(2*n-1) \\ _Charles R Greathouse IV_, Jun 17 2017
%Y Cf. A000384, A002939, A152745, A152994.
%K easy,nonn
%O 0,2
%A _Omar E. Pol_, Jan 01 2009
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