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%I #19 Nov 27 2013 14:46:14
%S 48,96,160,240,288,336,448,480,576,720,960,1008,1344,1440,1728,2016,
%T 2160,2400,2640,2688,3168,3360,3456,3744,4320,4368,4480,5040,5280,
%U 5760,6336,6720,7200,7488,8640,8736,8800,9408,10080,10560,10800,11520,12096,12480
%N Positive numbers differing from next 2 greater squares by squares.
%C All terms are even. The sequence is infinite. E.g., positive terms of A173121 {48, 288, 960, 2400, 5040, 9408, 16128, 25920, 39600,...} is infinite subsequence of A218486. - _Zak Seidov_, Nov 26 2013
%C Another infinite subsequence is {96, 480, 1440, 3360, 6720, 12096, 20160, ...} = 96 *binomial(m,4) = 96*(positive terms in A000332). - _Zak Seidov_, Nov 26 2013
%H Zak Seidov, <a href="/A218486/b218486.txt">Table of n, a(n) for n = 1..1000</a>
%H E. J. Barbeau, <a href="http://dx.doi.org/10.4153/CMB-1985-040-9">Numbers differing from consecutive squares by squares</a>, Canad. Math. Bull. 28(1985), pp. 337-342.
%e 48 = 7^2 - 1^2 = 8^2 - 4^2.
%o (PARI) sq2(n) = {for (i=1, n, a = sqrtint(i) + 1; if (issquare(a^2-i) && issquare((a+1)^2-i), print1(i, ", ")););}
%Y Cf. A173121, A218485, A218487, A218488.
%K nonn
%O 1,1
%A _Michel Marcus_, Oct 30 2012
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