This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A338010 #12 Nov 24 2023 12:39:40 %S A338010 9,35,51,55,77,85,119,153,169,171,187,209,261,319,369,385,451,531,551, %T A338010 595,649,715,741,779,899,935,961,969,989,1105,1121,1189,1241,1309, %U A338010 1443,1469,1479,1711,1829,1989,2001,2047,2091,2261,2345,2419,2555,2849,2915 %N A338010 Odd composite integers m such that A001109(m)^2 == 1 (mod m). %C A338010 For a, b integers, the generalized Lucas sequence is defined by the relation U(n+2)=a*U(n+1)-b*U(n) and U(0)=0, U(1)=1. %C A338010 This sequence satisfies the relation U(p)^2 == 1 for p prime and b=1,-1. %C A338010 The composite numbers with this property may be called weak generalized Lucas pseudoprimes of parameters a and b. %C A338010 The current sequence is defined for a=6 and b=1. %D A338010 D. Andrica and O. Bagdasar, Recurrent Sequences: Key Results, Applications and Problems. Springer (2020). %H A338010 D. Andrica and O. Bagdasar, <a href="https://repository.derby.ac.uk/item/92yqq/on-some-new-arithmetic-properties-of-the-generalized-lucas-sequences">On some new arithmetic properties of the generalized Lucas sequences</a>, preprint for Mediterr. J. Math. 18, 47 (2021). %t A338010 Select[Range[3, 3000, 2], CompositeQ[#] && Divisible[ChebyshevU[#-1, 3]*ChebyshevU[#-1, 3] - 1, #] &] %Y A338010 Cf. A338007 (a=3, b=1), A338008 (a=4, b=1), A338009 (a=5, b=1), A338011 (a=7, b=1). %K A338010 nonn %O A338010 1,1 %A A338010 _Ovidiu Bagdasar_, Oct 06 2020