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%I #18 Sep 08 2022 08:46:07
%S 1,992,3965,8920,15857,24776,35677,48560,63425,80272,99101,119912,
%T 142705,167480,194237,222976,253697,286400,321085,357752,396401,
%U 437032,479645,524240,570817,619376,669917,722440,776945,833432,891901,952352,1014785,1079200
%N a(n) = 991*n^2 + 1.
%C a(n) is nonsquare for 1 <= n < 12055735790331359447442538767.
%H <a href="/index/Rec#order_03">Index entries for linear recurrences with constant coefficients</a>, signature (3,-3,1).
%F G.f.: (1 + 989*x + 992*x^2)/(1 - x)^3.
%F a(n) = a(n-1) + 991*(2*n - 1).
%p seq(991*n^2+1, n=0..33);
%t Table[991*n^2 + 1, {n, 0, 33}]
%o (Magma) [991*n^2+1: n in [0..33]];
%o (PARI) for(n=0, 33, print1(991*n^2+1, ", "));
%Y Cf. A154651.
%K nonn,easy
%O 0,2
%A _Arkadiusz Wesolowski_, Feb 16 2014
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