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%I #12 Sep 08 2022 08:45:09
%S 1,17,97,241,449,721,1057,1457,1921,2449,3041,3697,4417,5201,6049,
%T 6961,7937,8977,10081,11249,12481,13777,15137,16561,18049,19601,21217,
%U 22897,24641,26449,28321,30257,32257,34321,36449,38641,40897,43217,45601
%N Third row of Pascal-(1,7,1) array A081582.
%H Vincenzo Librandi, <a href="/A081593/b081593.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) = 1-16*n+32*n^2.
%F G.f.: (1+7*x)^2/(1-x)^3.
%t CoefficientList[Series[(1 + 7 x)^2 / (1 - x)^3, {x, 0, 40}], x] (* _Vincenzo Librandi_, Aug 09 2013 *)
%o (Magma) [1-16*n+32*n^2: n in [0..40]]; // _Vincenzo Librandi_, Aug 09 2013
%o (PARI) a(n)=32*n^2-16*n+1 \\ _Charles R Greathouse IV_, Jun 17 2017
%Y Cf. A017077, A081594.
%K easy,nonn
%O 0,2
%A _Paul Barry_, Mar 23 2003