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 A301622 #27 May 11 2019 16:12:05
%S A301622 13,31,49,67,103,121,139,157,193,211,229,247,283,301,319,337,373,391,
%T A301622 409,427,463,481,499,517,553,571,589,607,643,661,679,697,733,751,769,
%U A301622 787,823,841,859,877,913,931,949,967,1003,1021,1039,1057,1093,1111
%N A301622 Numbers not divisible by 2, 3 or 5 (A007775) with digital root 4.
%C A301622 Numbers == {13, 31, 49, 67} mod 90 with additive sum sequence 13{+18+18+18+36} {repeat ...}. Includes all prime numbers > 5 with digital root 4.
%H A301622 Colin Barker, <a href="/A301622/b301622.txt">Table of n, a(n) for n = 1..1000</a>
%H A301622 <a href="/index/Rec#order_05">Index entries for linear recurrences with constant coefficients</a>, signature (1,0,0,1,-1).
%F A301622 Numbers == {13, 31, 49, 67} mod 90.
%F A301622 From _Colin Barker_, Mar 25 2018: (Start)
%F A301622 G.f.: x*(13 + 18*x + 18*x^2 + 18*x^3 + 23*x^4) / ((1 - x)^2*(1 + x)*(1 + x^2)).
%F A301622 a(n) = a(n-1) + a(n-4) - a(n-5) for n>5.
%F A301622 (End)
%t A301622 Rest@ CoefficientList[Series[x (13 + 18 x + 18 x^2 + 18 x^3 + 23 x^4)/((1 - x)^2*(1 + x) (1 + x^2)), {x, 0, 50}], x] (* _Michael De Vlieger_, Apr 21 2018 *)
%t A301622 LinearRecurrence[{1,0,0,1,-1},{13,31,49,67,103},50] (* _Harvey P. Dale_, May 11 2019 *)
%o A301622 (PARI) Vec(x*(13 + 18*x + 18*x^2 + 18*x^3 + 23*x^4) / ((1 - x)^2*(1 + x)*(1 + x^2)) + O(x^60)) \\ _Colin Barker_, Mar 25 2018
%o A301622 (GAP) Filtered(Filtered([1..1200],n->n mod 2 <> 0 and n mod 3 <> 0 and n mod 5 <> 0),i->i-9*Int((i-1)/9)=4); # _Muniru A Asiru_, Apr 22 2018
%Y A301622 Intersection of A007775 and A017209.
%K A301622 nonn,base,easy
%O A301622 1,1
%A A301622 _Gary Croft_, Mar 24 2018
%E A301622 Last term corrected by _Colin Barker_, Mar 25 2018