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%I #33 Apr 23 2021 12:14:51
%S 2,128,1458,8192,31250,93312,235298,524288,1062882,2000000,3543122,
%T 5971968,9653618,15059072,22781250,33554432,48275138,68024448,
%U 94091762,128000000,171532242,226759808,296071778,382205952,488281250,617831552
%N Bhaskara twins: n such that 2*n^2 = X^3 and 2*n^3 = Y^2.
%D S. S. Gupta, 'Bhaskara Pairs' in 'Science Today' (subsequently renamed '2001'), January 1988, pp. 68, Times of India, Mumbai.
%H Reinhard Zumkeller, <a href="/A106318/b106318.txt">Table of n, a(n) for n = 1..10000</a>
%H Richard J. Mathar, <a href="https://arxiv.org/abs/1703.01677">Construction of Bhaskara Pairs</a>, arXiv:1703.01677 [math.NT], 2017.
%H <a href="/index/Rec#order_07">Index entries for linear recurrences with constant coefficients</a>, signature (7,-21,35,-35,21,-7,1).
%F a(n) = 2*n^6 = 2*A001014(n).
%F G.f.: 2*(1+x)*(1+56*x+246*x^2+56*x^3+x^4)/(1-x)^7. - _Colin Barker_, Apr 18 2012
%F a(n) = 7*a(n-1)-21*a(n-2)+35*a(n-3)-35*a(n-4)+21*a(n-5)-7*a(n-6)+a(n-7). - _Wesley Ivan Hurt_, Apr 23 2021
%t LinearRecurrence[{7,-21,35,-35,21,-7,1},{2,128,1458,8192,31250,93312,235298},30] (* _Harvey P. Dale_, May 11 2017 *)
%o (PARI) a(n)=2*n^6 \\ _Charles R Greathouse IV_, Feb 09 2012
%o (Haskell)
%o a106318 = (* 2) . (^ 6) -- _Reinhard Zumkeller_, May 27 2015
%Y Cf. A106319, A106320, A106321, A106322.
%Y Cf. A001014.
%K nice,nonn,easy
%O 1,1
%A _Lekraj Beedassy_, Apr 29 2005
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