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%I #34 Feb 10 2023 10:50:45
%S 0,1,75,222,442,735,1101,1540,2052,2637,3295,4026,4830,5707,6657,7680,
%T 8776,9945,11187,12502,13890,15351,16885,18492,20172,21925,23751,
%U 25650,27622,29667,31785,33976,36240,38577,40987,43470,46026,48655,51357,54132,56980,59901,62895,65962,69102,72315,75601,78960,82392,85897,89475
%N 75-gonal numbers: a(n) = n*(73*n-71)/2.
%H Daniel Starodubtsev, <a href="/A098230/b098230.txt">Table of n, a(n) for n = 0..10000</a>
%H <a href="/index/Pol#polygonal_numbers">Index to sequences related to polygonal numbers</a>
%H <a href="/index/Rec#order_03">Index entries for linear recurrences with constant coefficients</a>, signature (3,-3,1).
%F G.f.: -x*(1+72*x) / (x-1)^3. - _R. J. Mathar_, Feb 05 2011
%F a(n) = n*(73*n - 71)/2.
%F E.g.f.: exp(x)*(x + 73*x^2/2). - _Nikolaos Pantelidis_, Feb 10 2023
%p A098230 := proc(n) n*(73*n-71)/2 ; end proc:
%p seq(A098230(n),n=0..20) ; # _R. J. Mathar_, Feb 04 2011
%o (Magma) [ n*(73*n - 71)/2: n in [0..50] ]; // _Vincenzo Librandi_, Feb 04 2011
%o (PARI) a(n)=n*(73*n-71)/2 \\ _Charles R Greathouse IV_, Oct 16 2015
%Y Cf. A051867, A051873.
%K nonn,easy
%O 0,3
%A _Parthasarathy Nambi_, Oct 25 2004
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