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<TITLE>Scaled Chebyshev U-polynomials evaluated at sqrt(3)/2</TITLE>
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<DIV>Dear SeqFans,</DIV>
<DIV>just submitted A105822 (see below). </DIV>
<DIV> </DIV>
<DIV>My request to SEQGurus:</DIV>
<DIV>Is it a permutation of positive integers? <BR>Among first 2000 terms,
</DIV>
<DIV>first missing numbers are 233, 349, 394, 443, 449. </DIV>
<DIV>Thanks,</DIV>
<DIV>Zak</DIV>
<DIV> </DIV>
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<DIV><FONT size=2>%I A105822<BR>%S A105822
<BR>1,2,3,5,8,4,12,7,10,17,6,11,21,32,13,19,14,33,20,28,24,27,42,40,18,9,35,44,39,54,48,22,15,37,</FONT></DIV>
<DIV><FONT
size=2>52,89,30,59,23,36,99,70,16,86,47,45,92,65,157,34,123,135,222,56,136,82,29,53,102,155,25,130,</FONT></DIV>
<DIV><FONT
size=2>87,43,170,213,63,150,57,66,96,72,60,100,125,111,236,91,145,74,71,154,177,81,258,95,112,64,</FONT></DIV>
<DIV><FONT size=2>156,55,50,105,98,203,31,84,115,106,77,183,144,327<BR>%N
A105822 For n > 2, a(n) > 0 not appeared previously is such
that </FONT></DIV>
<DIV><FONT size=2>a(n-1)^2+4*a(n-2)*a(n)=d^2 is a minimal square, a(1)=1,
a(2)=2.<BR>%C A105822 Is it a permutation of positive integers? </FONT></DIV>
<DIV><FONT size=2>Among first 2000 terms, first missing numbers are 233, 349,
394, 443, 449. </FONT></DIV>
<DIV><FONT size=2>The sequence depends on seed terms a(1) and a(2); if a(1) =
1, a(3) = a(2)+1. </FONT></DIV>
<DIV><FONT size=2>Values of d^2 in A105823. Cf. A105734.<BR>%Y A105822
A105734, A105823.<BR>%O A105822 1<BR>%K A105822 ,nonn,<BR>%A A105822 Zak
Seidov (<A
href="/ym/Compose?To=zakseidov@yahoo.com&YY=20090&order=down&sort=date&pos=0">zakseidov@yahoo.com</A>),
Apr 22 2005<BR></DIV></FONT></BLOCKQUOTE>
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