cp's OEIS Frontend

A296287 Solution of the complementary equation a(n) = a(n-1) + a(n-2) + n*b(n-2), where a(0) = 2, a(1) = 3, b(0) = 1, and (a(n)) and (b(n)) are increasing complementary sequences.

%I A296287 #4 Dec 14 2017 14:22:17
%S A296287 2,3,7,22,49,101,198,362,640,1101,1861,3105,5134,8434,13792,22481,
%T A296287 36561,59365,96286,156050,252796,409350,662696,1072644,1735988,
%U A296287 2809332,4546074,7356216,11903158,19260302,31164450,50425806,81591376,132018370,213611004
%N A296287 Solution of the complementary equation a(n) = a(n-1) + a(n-2) + n*b(n-2), where a(0) = 2, a(1) = 3, b(0) = 1, and (a(n)) and (b(n)) are increasing complementary sequences.
%C A296287 The increasing complementary sequences a() and b() are uniquely determined by the titular equation and initial values. a(n)/a(n-1) -> (1 + sqrt(5))/2 = golden ratio (A001622). See A296245 for a guide to related sequences.
%H A296287 Clark Kimberling, <a href="/A296287/b296287.txt">Table of n, a(n) for n = 0..1000</a>
%H A296287 Clark Kimberling, <a href="https://cs.uwaterloo.ca/journals/JIS/VOL10/Kimberling/kimberling26.html">Complementary equations</a>, J. Int. Seq. 19 (2007), 1-13.
%e A296287 a(0) = 2, a(1) = 3, b(0) = 1, b(1) = 4, b(2) = 5
%e A296287 a(2) = a(0) + a(1) + 2*b(0) = 7
%e A296287 Complement: (b(n)) = (1, 4, 5, 6, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 23, ...)
%t A296287 a[0] = 2; a[1] = 3; b[0] = 1;
%t A296287 a[n_] := a[n] = a[n - 1] + a[n - 2] + n*b[n-2];
%t A296287 j = 1; While[j < 10, k = a[j] - j - 1;
%t A296287  While[k < a[j + 1] - j + 1, b[k] = j + k + 2; k++]; j++];
%t A296287 Table[a[n], {n, 0, k}]; (* A296287 *)
%t A296287 Table[b[n], {n, 0, 20}]    (* complement *)
%Y A296287 Cf. A001622, A296245.
%K A296287 nonn,easy
%O A296287 0,1
%A A296287 _Clark Kimberling_, Dec 14 2017