# Greetings from The On-Line Encyclopedia of Integer Sequences! http://oeis.org/

Search: id:a294382
Showing 1-1 of 1

%I A294382 #11 Nov 06 2018 04:15:48
%S A294382 1,3,5,19,113,790,6319,56870,568699,6255688,75068255,975887314,
%T A294382 13662422395
%N A294382 Solution of the complementary equation a(n) = a(n-1)*b(n-2) - 1, where a(0) = 1, a(1) = 3, b(0) = 2, b(1) = 4.
%C A294382 The complementary sequences a() and b() are uniquely determined by the titular equation and initial values. See A294381 for a guide to related sequences.
%H A294382 Clark Kimberling, <a href="https://cs.uwaterloo.ca/journals/JIS/VOL10/Kimberling/kimberling26.pdf">Complementary equations</a>, J. Int. Seq. 19 (2007), 1-13.
%e A294382 a(0) = 1, a(1) = 3, b(0) = 2, b(1) = 4, so that
%e A294382 a(2)  = a(1)*b(0) - 1 = 5
%e A294382 Complement: (b(n)) = (2, 4, 6, 7, 8, 9, 10, 12, 13, 14, 15, 16, ...)
%t A294382 mex := First[Complement[Range[1, Max[#1] + 1], #1]] &;
%t A294382 a[0] = 1; a[1] = 3; b[0] = 2; b[1] = 4;
%t A294382 a[n_] := a[n] = a[n - 1]*b[n - 2] - 1;
%t A294382 b[n_] := b[n] = mex[Flatten[Table[Join[{a[n]}, {a[i], b[i]}], {i, 0, n - 1}]]];
%t A294382 Table[a[n], {n, 0, 40}]  (* A294382 *)
%t A294382 Table[b[n], {n, 0, 10}]
%Y A294382 Cf. A293076, A293765, A294381.
%K A294382 nonn,more
%O A294382 0,2
%A A294382 _Clark Kimberling_, Oct 29 2017

# Content is available under The OEIS End-User License Agreement: http://oeis.org/LICENSE