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%I #15 Sep 08 2022 08:46:14
%S 37,50653,69343957,94931877133,129961739795077,177917621779460413,
%T 243569224216081305397,333446267951815307088493,
%U 456487940826035155404146917,624931990990842127748277129373,855531895666462872887391390111637,1171223165167387672982838813062831053
%N a(n) = 37^(2*n+1).
%C 37*a(n) is a square.
%H G. C. Greubel, <a href="/A262786/b262786.txt">Table of n, a(n) for n = 0..250</a>
%H <a href="/index/Rec#order_01">Index entries for linear recurrences with constant coefficients</a>, signature (1369).
%F G.f.: 37/(1 - 1369*x).
%F a(n) = 1369*a(n-1).
%F a(n) = A009981(A005408(n)). - _Wesley Ivan Hurt_, Sep 04 2022
%t 37^Range[1, 30, 2]
%o (Magma) [37^(2*n+1): n in [0..15]];
%o (PARI) vector(20, n, n--; 37^(2*n+1)) \\ _Altug Alkan_, Oct 08 2015
%Y Second bisection of A009981 (powers of 37).
%Y Cf. similar sequences listed in A262715.
%Y Cf. A005408, A009981.
%K nonn,easy
%O 0,1
%A _Vincenzo Librandi_, Oct 08 2015