Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).
%I #14 Nov 27 2023 00:15:30
%S 1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,
%T 27,28,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,
%U 51,52,53,54,55,56,57,59,60,61,62,63,64,65,66,67,68,69,70,71,72,73,74
%N Not divisible by 29.
%H <a href="/index/Rec#order_29">Index entries for linear recurrences with constant coefficients</a>, signature (1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, -1).
%F From _Chai Wah Wu_, Aug 04 2016: (Start)
%F a(n) = a(n-1) + a(n-28) - a(n-29) for n > 29.
%F G.f.: Sum_{k = 1..29} x^k /(1 - x - x^28 + x^29). (End)
%t With[{nn=100},Complement[Range[nn],Range[29,nn,29]]] (* _Harvey P. Dale_, Mar 11 2013 *)
%o (Sage) [i for i in range(0,100) if gcd(29, i) == 1]
%K nonn,easy
%O 1,2
%A _Zerinvary Lajos_, May 18 2009