%I #15 Sep 08 2022 08:46:19

%S 15,35,55,75,95,115,135,155,175,195,215,235,255,275,295,315,335,355,

%T 375,395,415,435,455,475,495,515,535,555,575,595,615,635,655,675,695,

%U 715,735,755,775,795,815,835,855,875,895,915,935,955,975,995,1015,1035

%N a(n) = 20*n + 15.

%C Bisection of A017329.

%C None of the numbers in this sequence is a Fermat pseudoprime to base 2.

%H <a href="/index/Rec#order_02">Index entries for linear recurrences with constant coefficients</a>, signature (2,-1).

%F G.f.: 5*(3 + x)/(1 - x)^2.

%F a(n) = A004767(A016885(n)) = A004767(A004767(n) + n). - _Torlach Rush_, Oct 10 2019

%F E.g.f.: 5*exp(x)*(3 + 4*x). - _Stefano Spezia_, Oct 12 2019

%t Range[15, 1035, 20]

%o (Magma) [n: n in [15..1035 by 20]];

%Y Cf. A001567, A004767, A016885, A017329.

%K nonn,easy

%O 0,1

%A _Arkadiusz Wesolowski_, Aug 10 2017