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%I #37 Mar 18 2022 05:21:06
%S 2,3,6,11,14,15,18,23,26,27,30,35,38,39,42,47,50,51,54,59,62,63,66,71,
%T 74,75,78,83,86,87,90,95,98,99,102,107,110,111,114,119,122,123,126,
%U 131,134,135,138,143,146,147,150,155,158,159,162,167,170,171,174
%N Numbers congruent to 2, 3, 6, 11 mod 12.
%H <a href="/index/Rec#order_04">Index entries for linear recurrences with constant coefficients</a>, signature (2,-2,2,-1).
%F a(n) = 2a(n-1) - 2a(n-2) + 2a(n-3) - a(n-4). - _Charles R Greathouse IV_, Nov 09 2012
%F G.f.: x^2*(x^3+4*x^2-x+2) / ((x-1)^2*(x^2+1)). - _Colin Barker_, Jan 07 2013
%F {m>1|C(m,4)==0 (mod C(m,2))}. - _Gary Detlefs_, Jan 11 2014
%F Sum_{n>=1} (-1)^(n+1)/a(n) = (2*sqrt(3)+1)*Pi/24 - log(2+sqrt(3))/(4*sqrt(3)) - log(2)/6. - _Amiram Eldar_, Mar 18 2022
%t LinearRecurrence[{2, -2, 2, -1}, {2, 3, 6, 11}, 100] (* _T. D. Noe_, Nov 11 2012 *)
%o (PARI) for(m=2,175,if(binomial(m,4)%binomial(m,2)==0,print1(m,", "))) \\ _Hugo Pfoertner_, Aug 11 2020
%Y Cf. A042944, A042945.
%K nonn,easy
%O 1,1
%A _Jean-Claude Babois_, Oct 22 2012
%E Edited by _Andrey Zabolotskiy_, Aug 11 2020