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 A166259 Positive integers n such that a centered polygonal number nk(k+1)/2+1 is not a square for any k>0. 2

%I

%S 2,18,32,50,72,98,128,162,200,242,338,392,450,512,578,648,722,882,968,

%T 1058,1152,1250,1352,1458,1682,1800,1922,2048,2178,2312,2401,2450,

%U 2662,2738,2809,2888,3042,3174,3200,3362,3528,3698,3750,4050,4225,4232,4418,4489,4608,4802

%N Positive integers n such that a centered polygonal number nk(k+1)/2+1 is not a square for any k>0.

%C Positive integers n such that A120744(n) = -1.

%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/CenteredPolygonalNumber.html">Centered Polygonal Number</a>.

%Y Cf. A120744, A001542, A006451, A001921, A129444, A001570, A001652, A129556, A053606, A105038, A105040, A053141, A061278.

%K nonn

%O 1,1

%A _Alexander Adamchuk_, Oct 10 2009

%E Edited and extended by _Max Alekseyev_, Jan 20 2010

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Last modified April 12 17:26 EDT 2021. Contains 342929 sequences. (Running on oeis4.)