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%I #11 Nov 20 2018 02:55:39
%S 1,3,6,19,30,51,70,99,157,167,233,343,386,455,506,583,642,727,794,887,
%T 1138,1671,1693,1788,1933,2036,2453,2731,2745,3031,3053,3508,3717,
%U 4027,4073,4391,4825,4976,5225,5384,5641,5808,6073,6471,6754,6935,7226,7903
%N Numbers in increasing order such that successive sums are squares and successive differences are squarefree.
%C a(n) > a(n-1), a(n) + a(n-1) is a square, a(n) - a(n-1) is squarefree.
%H Vincenzo Librandi, <a href="/A090956/b090956.txt">Table of n, a(n) for n = 0..1000</a>
%e 103 follows 93 as 103 - 93 = 10 is squarefree and 93 + 103 = 196 = 14^2.
%t <<NumberTheory`; a = 1; Print[a]; Do[k = a + 1; While[ !(SquareFreeQ[k - a] && IntegerQ[Sqrt[k + a]]), k++ ]; a = k; Print[a], {n, 1, 100}] (* _Ryan Propper_, Aug 27 2005 *)
%Y Cf. A090955.
%K nonn
%O 0,2
%A _Amarnath Murthy_, Dec 31 2003
%E Corrected and extended by _Ryan Propper_, Aug 27 2005
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