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%I #30 May 13 2019 09:03:51
%S 1,3,5,6,7,9,11,13,14,15,17,19,21,22,23,25,27,29,30,31,33,35,37,38,39,
%T 41,43,45,46,47,49,51,53,54,55,57,59,61,62,63,65,67,69,70,71,73,75,77,
%U 78,79,81,83,85,86,87,89,91,93,94,95,97,99,101,102,103,105,107
%N Numbers that are congruent to {1, 3, 5, 6, 7} mod 8.
%C Numbers n such that A232713(n) is divisible by n. [_Bruno Berselli_, Dec 11 2013]
%H <a href="/index/Rec#order_06">Index entries for linear recurrences with constant coefficients</a>, signature (1,0,0,0,1,-1).
%F G.f.: (1 + x)*(1 + x + x^2 + x^4) / ((1 - x)^2*(1 + x + x^2 + x^3 + x^4)). [_Bruno Berselli_, Dec 11 2013]
%F From _Wesley Ivan Hurt_, Dec 30 2016: (Start)
%F a(n) = a(n-1) + a(n-5) - a(n-6) for n > 6.
%F a(n) = (40n - 10 + 3*(n mod 5) + 3*((n+1) mod 5) - 2*((n+2) mod 5) - 2*((n+3) mod 5) - 2*((n+4) mod 5))/25. (End)
%t Select[Range@ 107, Or[OddQ@ Mod[#, 8], Mod[#, 8] == 6] &] (* _Michael De Vlieger_, Oct 23 2015 *)
%t #+{1,3,5,6,7}&/@(8*Range[0,20])//Flatten (* _Harvey P. Dale_, May 13 2019 *)
%o (PARI) x='x+O('x^100); Vec((1+x)*(1+x+x^2+x^4)/((1-x)^2*(1+x+x^2+x^3+ x^4))) \\ _Altug Alkan_, Oct 22 2015
%Y Cf. A232713.
%K nonn,easy
%O 1,2
%A _N. J. A. Sloane_
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